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NZ Sidewinder
11-28-2020, 03:40 AM
My name is Phillip and Im from New Zealand in the deep south Pacific down below and East of Australia.
We are a small country of 5 million people but have a similar length of coastline as the USA so we are a boating Nation.
My background is in Engineering and design but these days I am a manufacturer of a Product.
At heart Im an innovator so rather go out and buy a ready made fast boat I like to build or adapt things and have had a few good boats over the yrs , mainly Axial flow jets (Hamiltons/ Kodiak) (Small block Chevs)
The Panther/Sidewinder is an iconic boat here and most if not all are rotten so it made sense to me to restore one.
I have two Sons that are keen boaties and they wanted a chick magnet to ski with so the 22YO sent me a link to this one for sale and here we are.
My current boat is what is known here as a Fryan 440 deep Vee which is a 4.4m Aluminium fishing boat that weighs about 280lbs plus motor (40hp Merc XR Lightning).
Its a good little fishing boat and will pull me up from a deep water start on a single ski but is no Chick magnet, especially with a name like "Bart".
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This is the third thread related to this rebuild but I feel this thread is probably the right place.
There is a background story so Ill start back a bit, around the early 1970's.
In New Zealand early in the 70's a sleek new ski boat appeared around the ski lanes of Lake Taupo.
It was different than anything Id seen before and was called a Panther, manufactured by Plylite.
As a 12yr old I decided that whoever designed this thing was light years ahead of the rest.

Later I learned that the Panther was a close copy of the sidewinder and didn't originate from New Zealand at all.
This particular boat is a Plylite Panther and in NZ they carried the cast and chromed leaping cat emblem just below the gunnel.
The panther also had a racy instrument mount in the center of the Dash.
They were a mass produced ski boat that came new with Evenrudes from 115hp to 140hp and were probably good for around 45-50mph.
When you start to pull one to pieces it becomes apparent that they weren't manufactured with racing in mind, in fact they were very average IMO.
It appeared that this particular boat was assembled by a team of two fibreglass guys, one doing the port side and the other Starboard.
The starboard side was not too bad and the Port side absolute ****.
The Port side was very easy to dismantle, it basically fell to pieces because none of the glued components had bonded properly.

The boat was purchased from a family that had had it for 30yrs and was described as original which it was.
The motor was described as not going due to ignition problems but was tired also.
This was all correct and the motor was scraped.
The trailer was described as very poor but in fact it is very good and not requiring much work at all.
Ive built lots of trailers in my time and the seller got this part really wrong.

I paid 3k for the lot and towed it home.
It was obvious before I brought it that the transom was rotten but thats a good thing because it would be a shame to rip out a good one and the transom was coming out no matter what.
The job and photos start with a clean out of 30yrs of artifacts, the boat was a time capsule full of all sorts of old stuff.
Old bottles of tanning oil, old life jackets and very old goggles and snorkel sets.
bundles of small ropes, and old divers knief and various tools.
The owner told me that as the boat aged it got slower and this could have been due to increased weight.

So the photos start with the clean out477922

Then the Motor comes off477923

Then the transom starts to come out477924

Then the floor and Stringers477925
477926

Then the Boat needed to be set up in a jig to ensure the hull went back together in a near to original shape but in my opinion the original lines were so far out of whack that it would be a matter of just getting it close and then putting enough glass on the inside that the hull could be blueprinted from the outside later
477927477928

Then the transom and all the structure needed to be mocked up.
The ply pad in the keel here is the top of the pad and not a tunnel as it may appear to be.
This part is 8 inches wide but the total pad and tunnel width will be 13 inches.
The underside of that beam is the top of the tunnel as shown in the sketch
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The silver Fat Max level shows the new floor level which is 3 1/4 inches higher than the original floor allowing for much deeper stringers and broader structure to resist torque loads on hull.
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The transom is 3 layers of 18mm marine ply thats about 2.5 inches and the floor of the transom well is 1/2 inch ply which will be well attached to the Transom and also to the Transom Knee which is attached or part of the 6 inch keel stringer so the motor will never fall off not even the way I drive.

This is where Im up to so far

tnelsmn
11-28-2020, 10:26 AM
Cool old boat! Looking forward to seeing it come together.

keefallan
12-02-2020, 05:24 AM
Welcome to S/F!! Keep posting the restoration........it looks good.

NZ Sidewinder
12-02-2020, 01:54 PM
Thanks
Yes ill keep posting updates until the boat is cornering hard around Bouys.
If I stop posting it's because the Boat didn't make the turn ..Lol

NZ Sidewinder
12-03-2020, 09:36 PM
Today I visited the local fibre glass shop to talk about construction joint adhesives and the guy showed me a 2 pot product he uses.
Its a tricky name to remember and it isnt an epoxy.
It is slightly flexible and will stick well to Polyester.
He said that its so strong that bulkheads can be glued and coved with it and thats enough.
So Im going to use it to bed and cove my stringers but also glass over the cove.
He also said he prefers to bolt the main transom knee of rough water boats which suits me because Ive spent my life bolting things.

We also spoke about sidewinders and Panthers.
He reckoned the NZ sidewinder was better built than the Panther and thats why most of the raced ones were Sidewinders and he told me about the mold defect in the Panthers which didn't find its way into the Sidewinders.
Look at the Chines where they meet.
I dont know how a company could allow a 1000 hulls to be built like this.478400

NZ Sidewinder
12-08-2020, 03:09 AM
The Transom is now encapsulated and ready for the knees and well to be attached.
The Hull is now the focus to get ready to accept the transom.
Lots and lots of work that takes a while to show results.
Reminds me of building houses, they take lots of time and money to get up out of the ground.478661
This is the outside face of the transom and needs another 8, maybe 10 layers of glass once glued in

NZ Sidewinder
12-13-2020, 04:03 AM
A little more progress for a lot of hours.
All the knee to transom and Knee to Pad structural joints will be ply to ply rather than poly to poly.
Then coved etc in poly.
The Transom isnt glued in yet because I intend to attach all the knees and the transom well to the transom and fully glass all that detail while the transom is on the bench.
Once thats finished the unit will be fitted and the knees attached to stringers etc
479002479003479004

NZ Sidewinder
12-13-2020, 05:49 AM
Ply and Glass is good to work with but having got this far I now appreciate Aluminium and steel.
They are so easy and quick to fabricate with.
The ideal boat would IMO have a molded glass top side and Alloy Hull.

XstreamVking
12-14-2020, 07:15 AM
Nice neat glass work. It takes some time working with glass to appreciate how versatile it is. I have used it on houses and have even made emergency repairs on industrial plumbing with it.

NZ Sidewinder
12-16-2020, 03:35 AM
Im trying this Glue
Crestomer 1152PA-P
Synthepol

Its a 2 pot (MEKP) gel that is compatible with Polyester

NZ Sidewinder
12-19-2020, 10:35 PM
479298479299The knees are now glued to the transom and the Transom Well floor is attached to the transom and also the top of the keel knee.
The two outside knees are attached to transom also.
None of this is yet glued to the hull as it will all be lifted out as a unit and fully glassed on the bench then fitted back in and glued and glassed to the hull.
There is a long 12mm Stainless bolt through the top of the keel knee and transom.
This 12mm bolt is in a 16mm (5/8) s/s tube that has a flange at the transom end so it can be sealed.
I may use the same detail for the engine bracket bolts also.

The spirit level is floor level479293






479292

NZ Sidewinder
12-21-2020, 04:28 AM
Transom is now out to be finished before being glued and glassed back in.
All the ply will be encapsulated then re fitted and attached to the stringers 479332
etc.
It will also get some floor support cleats.
479333

NZ Sidewinder
12-30-2020, 06:20 PM
Transom glued in with Crestomer 1152 A-P
Heaps of work yet but this is a milestone479943479944
The transom has a cove to the hull and will be glassed in as well.

tnelsmn
12-31-2020, 11:03 PM
Looking good!

NZ Sidewinder
01-03-2021, 03:41 AM
480103
Stock these boats are as rigid as a plate of jelly and the more I get into this one the more I realize they were designed as show ponies not race boats.
Here the sides are getting some knees.

NZ Sidewinder
01-10-2021, 05:39 AM
Today I started getting the stringers sorted.
The Keel Stringer has been joined using 12mm ply epoxied fish plates, the next two out are the same and the next two stop at the 8ft mark.
All will be fully encapsulated except for the upper edge which will be glasses after the stringers have been machined down to a finished height for the floor to glue to.
Each stringer sits in a strake so Ill lay extra glass in the strake recesses and out over the hull.
The Hull bottom will end up 1/4 inch thick which is heavy but it wont break.
480406

NZ Sidewinder
02-07-2021, 08:48 PM
Ive made some progress now.
The stringers were a massive job and next time Ill use a composite instead of encapsulated plywood.
Ive used a lot of Urethane adhesive and also epoxy in this build.
The Urethane is a very good adhesive/cove/ gap filler.
My plan is to shift the drivers position back at least 14 inches and extend the steering column.
Id estimate that 150hrs went into the stringers and floor alone and I still need to tip the boat over and fabricate/blueprint the bottom.
Im aiming for a 100mph river boat and 70mph offshore boat.
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The stringers have fish plates at the joins that are polyester encapsulated, epoxied on then coved and glassed in.
Keel stringer has fishplate reinforcing over the step and there are lots of cleats on the stringers for extra floor gluing.

482049

482050
Now Im doing the small fiddly bits of topside finishing including glassing all the floor edges and seams.
Ill also add a pair of sidewall knees midships.

NZ Sidewinder
02-21-2021, 05:01 AM
Stern corners back in place now.
There is a lot of structural glass and then fiddly details in the stern of this boat and it's going to be a relief to get out of the Hull and start work from the outside.
Having said that Ive now noted that the fore deck has some stress cracks across it from years of pounding on Lake Taupo's harsh chop.
Ill need to put a bulkhead up there and this can also support the bow flares which have been worrying me.
There is still 3/8 inch of 1708 mat to go on the outside of the transom yet.
Most of the structural connections including the floor and stringers and Coves use Urethane or Epoxy.
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NZ Sidewinder
03-03-2021, 01:50 AM
Basically the Hull is fully glassed now with just the bottom to finish the Pad and blueprint.
Then full paint etc.
The whole time Ive been dreading weighing the beast and today the 300kg crane scales arrived.
I hung th hull from the rafters and put the scales first in the bow sling which read 156kg (343lb)
Then in one stern corner and that was 139.5kg (307lb)x2
So thats a total bare hull weight of 439.5kg (967lb)
Heavy.
Shes going to need some serious hp

I also glasses up all the holes in the dash with new encapsulated backing ply.
The part where the steering column goes got 1 inch ply fully glassed in really strong so I can put a steering extension tube on and push the drivers seat well astern.
This also keeps the drivers thigh bones (Femur) well clear of the lower edge of the dash.
Ill never forget rebuilding an aluminium Jet boat hull for a bloke who insisted he put the unit back in himself.
He stuffed up the nozzle linkage or the bucket pivot and first corner in the river on the try out the steering jammed and he hit the bank at 55mph.
That bottom edge of the dash snapped both his femurs.
Im thinking 250hp 2 stroke Merc on a bracket.483385

Karsten
03-03-2021, 03:04 PM
483385[/ATTACH]

I don't know how they Rate Hulls down under.....here in the States I had to fight like hell to get the 2012 Merc Optimax 150 hung on the back of mine.

The shop wasn't going to do it, insurance wasn't going to cover the boat....One day the guy in the shop crawled around with a light and he could just make out Max HP 150 on the ID Tag.......

Here's some pic's for Motivation now get back to work.

https://imagizer.imageshack.com/v2/640x480q90/633/aqxwMz.jpg (https://imageshack.com/i/hlaqxwMzj)

https://imagizer.imageshack.com/v2/640x480q90/924/grihkQ.jpg (https://imageshack.com/i/pogrihkQj)

https://imagizer.imageshack.com/v2/640x480q90/923/BZxcVc.jpg (https://imageshack.com/i/pnBZxcVcj)

Get a 22-23 Pitch 4 Blade SS prop....the 3 blade drove like a school bus on a Ford I Beam Suspension and I couldn't get it to plane....Rode Rough in even the slightest chop so the GF shut me down at 25 MPH.

4 Blade pop out of the water, flies flat and take all the chop you can through at it....Even my own Wake and it throws a hell of a wake.

https://imagizer.imageshack.com/v2/640x480q90/921/mGgg0Q.jpg (https://imageshack.com/i/plmGgg0Qj)

Karsten

NZ Sidewinder
03-03-2021, 03:28 PM
Hi Karsten
Nice tidy boat you have.
Down here there are no rules about boats other than needing to be 15yr old to drive a boat capable of more than 5 knots.
Biggest problem here are Jet skis exceeding 5 knot close to shore.
Insurance is expensive for boats now and I insure for theft only.
This Sidewinder/Panther started out as a vintage restoration but quickly became a hot rod type project in that below the water line she is no longer a Sidewinder.
Down here these boats were often raced off shore with twin 150s or single 150s but were not a good boat to push fast with a single engine.
So I put a stepped pad in this one that will have side Dams that also add longitudinal edges too keep her straight and true at high speed.
Basically a copy of a famous NZ offshore race boat named Chindit.
Here is a photo of Chindit and also a link to a Utube Vid that makes my heart race every time I watch it.
My next build will be a copy of Chindit
https://www.youtube.com/watch?v=UfCBBNbZn3A

483406

NZ Sidewinder
03-11-2021, 02:15 AM
Today I put the boat back on the trailer for a better working height to finish the transom glass.
This is raw 1708 and it will get straightedge sanded and then Chop strand and Faired.
Ive added a mock up photo of the approximate profile of the Pad.
The tubes are urethaned in and are liners for the bung holes.
Once the Trasom and well are tidied up Ill turn the Hull over and start on the Bottom.483768483769

LakeFever
03-11-2021, 04:36 AM
Your build is coming out excellent! Why add the csm after straight edging the transom?

NZ Sidewinder
03-11-2021, 04:48 AM
Im not an expert in Fiber Glass but the general rule is to start with CSM and finish with CSM as the DB pattern can show through the paint.

LakeFever
03-11-2021, 09:02 AM
Sounds good to me, more glass is better than less glass

NZ Sidewinder
03-13-2021, 04:31 PM
Lol
More is better sometimes but I reckon Im pushing the envelope with this transom.
Here is a core from a bung hole.
483859

NZ Sidewinder
03-19-2021, 05:50 PM
This is the old motor that came with this boat.
Its been laying in the grass for a few months and I just couldn't work out how to stow it so I could easily cannibalize it before it goes to the dump.
So I filled this IBC with water (1 ton) and hug the thing on it aided by a load binder.
It could easily have a ply bench top and a basic timber mounting bracket but this works fine for now.
Even twins could be worked on or stored on one IBC or even Quads.
This motor weighs say 330lb but Im sure 500lb is doable with some small mods or additions.
one thing is for sure, 500lb wont tip the 2200lb IBC over and water is still cheap.484199

NZ Sidewinder
04-02-2021, 01:31 AM
484861Today she got tipped over and I wasted no time in diving in.
It was a good feeling to grind down through the old hull to find the new Pad/Tunnel484856484857484858484859484860

NZ Sidewinder
04-03-2021, 10:26 PM
484933
Today I spent a few hours surveying the hull bottom.
What a shambles.
Looking at the transom from the stern once the Hull had been leveled to the same datum as I used to do the inside work I wasn't really surprised that the optical level (dumpy level) showed that the starboard chine was lower at the transom than the port chine but the starboard strakes were higher at the transom than their opposites on the port side.
Basically the mold was pissed.
The hull has huge trailer Hooks out at the third strakes.
Also as shown in the photo by the yellow line the keel has a large bump in it near the entry 3/8 inch.
Is this likely to be a design feature??
I intend to recreate a knief edge vee from the trailer winch eye through to the step.
Looking at the Hull in its original form, it was a brave crew that took these boats anywhere near 70mph.
They were said to porpoise in the turns or not turn at all as well as get wobbly in a straight line.
It's all there in plain sight.
But even Steve Austin was just a regular guy until they threw 6 million bucks at him.

NZ Sidewinder
04-05-2021, 06:32 AM
484989Ive decided to put embedded stainless female threads into the flat pad area and form the tunnel with a Stainless or Aluminium sheet that fixes to the hull with countersunk bronze machine screws.
This way I can bolt on a variety of Hull forms by attaching them to the metal base.
In a stock form the plate will have a Dam along each edge as shown in green.
Once this is on, a few different forms can be added or subtracted such as a continuous Vee with dams or a delta Pad with Dams or even a radius Vee with dams.
If I want to race this boat in one particular racing organisation then I must not use a step in the particular class that would best suit this boat.
So for those races Id bolt in a delta Vee Pad which would have the same transom exit position but start at the top of the apex of the step.
Green is the metal base shape and what it would generally run.
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NZ Sidewinder
04-14-2021, 08:01 PM
485546Well I may have got lucky.
Picked this beast up today
1999 225 2.5 promax
135compressions
234 hrs
Un raced
Been used as driveway decoration
20 inch with spacer

OG857959
485528485529485530

tnelsmn
04-15-2021, 09:58 PM
Dang, nice ProMax! Must be something going around, I just picked one up in similar condition.
485585

NZ Sidewinder
04-16-2021, 01:48 AM
I weighed the Merc today
In 25 inch form with prop and oil injection = 192 kg (423lb)
In 20 inch form with prop and oil injection = 182kg (401lb)

1983 140hp Evinrude apples for apples about 150kg(330lb)

When I saw this beast I thought it would sink my boat but there really is nothing in it between the big Merc and the puny Evinrude.
Just over one and a half tot tanks of gas in weight but at least 100 real HP.485596

spybot
04-16-2021, 02:07 AM
Good to see the hull take shape.
I stay in Scotland and have a dateline "Bikini"
Similar hull so would defo like to see how the step pans out.
Mine has the trailer hook plus needs the entire floor lifted.
Keep up the good work.485597

NZ Sidewinder
04-16-2021, 02:58 AM
Great to see.
They look very similar and it would be interesting to see the point at the bow where the chines meet.
If the chines mismatch at the bow then the boats are genetically related.
The step and Pad are going to incorporate some unique features.
The pad will have a aluminium or stainless liner shaped like ] that.
Edges down.
Also embedded and epoxied in the step and pad will be threads for various hull forms.
eg
One race class doesn't allow steps so a delter pad will be bolted in
That this stage the metal plate and vertical dams will stay in place no matter what hull form is in place.
Even if a V is bolted in the plate and dams remain.
The motor will hang on a 10 or 12 inch set back bracket and the pad and supports will extend back that same amount so as to in effect lengthen the Hull and retain forward/ aft balance.
The Keel V forward of the step will likely be may sharper.

spybot
04-16-2021, 03:50 AM
I read about your idea of the bolt on add ons. Interesting bit of design work.
I take the ] will have the edges as a runners ? Sort of tunnel like ?
I have a rounded pad just now. Not the best i was getting some serious porpoising then chine walk around 50mph so added a set of trim tabs these corrected the faults. Hopefully by blueprinting the hull i will remove these.
Just now i have two of these hulls. One in the picture ready for restore. I have a mod 140 1980 johnson cnc jackplate with added 2" so total of 6"-8" setback. Not sure how the hull will handle the setback. The other boat has a 120 evinrude looper. She is out the hole like a bullet but still a bit shake around 55mph
Would like a boat to handle some chop. I stay on the coast but the coast is on the north sea. Not the most calm of water lol.
Keep the pictures and updates coming. Very keen to see how you get on.

Feel free to PM any other pics you have

Cheers

Andy

NZ Sidewinder
05-02-2021, 02:08 AM
This weekend I started the blueprinting of the Hull.
On a nice sunny Autumns day its an enjoyable task and one that needs to be finished before it gets too cold.
Ive spent a lot of time recently sorting the engine with a couple of spare lowers and a hydraulic jack plate.
One lower is Coned but doesn't have a low water pickup and the other two are going to get cones and one may even get carbon wrapped.
Both these two will have low water pickups.
The combined effect of a 14 degree raking transom and the jack plate will put the leg back at least 12 inches behind the lower edge of the transom so Im planing on extending the steel pad back to the bullet, effectively lengthening the hull.
This extension will be bolted to the main pad so can be tinkered with.486355486356486357

NZ Sidewinder
05-10-2021, 01:54 AM
While the weather is wet Im working on my lower units, 3 in total.
Two virgins and one coned.
The coned one had a split in the case through the nut thread and the other two are good but will need cones.
A race guy here described how he spent hours scratching out corroded threads so I got my brother to make a Tap to do the job.
The mandrel will likely be used for carrying a pinion setting disc as well (2,655 and 2. 575 inch).
Im keen to hear if anyone has ever made a cone by threading into the bull nose of the standard Bullet and attaching a machined Ali cone.
The lost wax method of creating the water galleries would be used to form the Car Bog within the hollowed out machined bullet.

There is 12mm of Ali in the casting at the forward end of the bullet to tap into.
Id say 3/8 UNC or 10mm.
My motor is now safely perched in the workshop ready for winter tinkering486688486689486690

NZ Sidewinder
05-15-2021, 01:15 AM
This is a C1 lower case that Ive taken the previous cone off as it didnt have a low water pick up.
This structure is the foundation of the new cone with a pick up.
The cylinder on the end of the bullet is the collection chamber and the back bone is the feed tube.
The collection chamber will have an aluminium cone that threads on and the pick up holes will be in that cone
It will get shimmed so that the pick up holes are in the correct orientation.
That 10mm s/s threaded rod is threaded into the gear case and sealed will locktite 577.
I made u drill guide that fits into the prop shaft bearing journal and a long series drill goes from the inside of the case, through the hollow guide and through the case perfectly on center.
The backbone tube will have small tabs on it and screws going into the leading edge of the case so that the bog and poly isnt the only structure holding everything in place.
At the top of the tube there will be a shaped cap and there will be two sockets welded off the sides of the tube down at the correct level as per normal. 486990

NZ Sidewinder
05-17-2021, 01:14 AM
A few more photos of the Gear case so far
The zinc washer represents the large diameter and position of the screw on nose piece.

487071487072487109

NZ Sidewinder
05-19-2021, 12:11 AM
This is the fun bit
487180487181487182
There is a lot of shaping and finishing to do yet and the Aluminium cone bullet point needs to be made but thats simple.
I do need to get some advice about the water intake to the pump.
When looking down into the water gallery with the pump removed there isnt much width available to drill and Tap a decent size hole for the fitting.
even 3/8 bsp would be a squeeze by the look of it.
The starboard side is the side with the most room but is still tight.
The port side is a really tight on a C1 at least.
It looks as if it would be necessary to cut away some of the cavitation plate also.
Any pointers on these issues??

NZ Sidewinder
05-19-2021, 11:03 PM
More shaping today and I made a wooden mock up bullet point to help with getting a good shape.
The wooden one can now be used to rough out an Aluminium one.
I think Ill wrap this unit in epoxy/glass or Carbon.487245487246487424

NZ Sidewinder
05-31-2021, 05:12 AM
Somewhere on this forum I read a post from an engine builder that he could build 2 engines in the time it took him to do a complete lower unit like this one.
Its amazing, the hours just vanish.
But there is progress, Ive shortened to driveshafts, stripped my mid section and ordered some parts out of the States, made a new short powerhead to plate stud, blasted and repainted my rusty steering yoke, cleaned up all the solid mounts and replaced one long bolt, shortened both the water tube and the gear select rod and cast an Epoxy bullet low water pickup and shaped it.
Not sure if the water holes are ideally positioned though.
487895487896

NZ Sidewinder
05-31-2021, 05:12 AM
Somewhere on this forum I read a post from an engine builder that he could build 2 engines in the time it took him to do a complete lower unit like this one.
Its amazing, the hours just vanish.
But there is progress, Ive shortened two driveshafts, stripped my mid section and ordered some parts out of the States, made a new short powerhead to plate stud, blasted and repainted my rusty steering yoke, cleaned up all the solid mounts and replaced one long bolt, shortened both the water tube and the gear select rod and cast an Epoxy bullet low water pickup and shaped it.
Not sure if the water holes are ideally positioned though.
487895487896

NZ Sidewinder
06-30-2021, 03:48 AM
These fishing Pro max motors are insanely difficult to fit with bullet proof offshore steering wings, the kind that can take the kind of punishment I tend to meter out.
But after 4 days head down arse up its almost done.
The wing is carried in part by the cowl plate but also substantially by a second horse shoe plate down at the level of the 3 large bolts that clamp the plates.
Ive changed the bolts out for studs and the lower horseshoe is held by these studs which can be extracted up through the three new holes in the cowl plate.
This enables the whole unit to be lifted off in one.
Between the cowl plate and the new lower horseshoe plate are 5/8 formed Aluminium packers.
The actual wing plates are slung below this mounting unit on solid Aluminium spacers.
This enables the Cowl base to fit on.
It wont break or bend Im sure of that.
Cant imagine another way of doing it.489669489670489671489672489673

LakeFever
06-30-2021, 04:29 AM
Wow, that’s a ton of work. Never seen anything like it. Hats off for the innovation

XstreamVking
06-30-2021, 06:27 AM
Very cool project. Making your own parts is so time consuming.

NZ Sidewinder
07-01-2021, 02:16 AM
Today I finished the wings and started back on the lower Unit.
The water feed tubes are tacked up.
The pipes almost meet in the middle and are coupled with sturdy rubber hose.
Also tapped the feed tube holes.
Someone at Mercury must have been thinking of us when then dimensioned that water gallery.
The final finishing of the epoxy on the unit can wait till last now.489729489730489731

NZ Sidewinder
07-26-2021, 04:21 AM
491104491105
Its been slow work but Im trying to just take my time and get it right.
Ive been making tools as well and putting the box together with old components just for practice and to work out where the traps are.
Tonight I worked out that a bit of heat into the bullet with a heat gun makes the main forward cone go in really easy.
No hitting required just a few taps on the tool.

I cut the inner race of the forward gear off with a grinder or at least ground the race down to paper thin on two opposite sides then used the puller to pull it while heating the thin parts with the heat gun.
In my early days I cut lots of these bearing races off with the oxy /acetylene torch.
Not a job for the faint hearted.

My pinion gauge tool locates on 3 places, the rear carrier ring, the main carrier ring and the forward bearing needle roller and also in the gear shift spigot journal if there is no gear in place.
The Carrier is bushed down to 32mm for the gauge shaft
The gauge is an adjustable 3/8 UNF bolt with lock nut.
The head of the bolt is polished spherical
Its set at a radius of half the 2.575inch.

Currently this box with a new drive shaft thrust bearing has 20 thou pinion clearance with a 30 thou shim so I need a 35 thou shim
Hope there is such a shim.

Ive got a good offshore midsection for my Promax but am going to put some serious work into designing a way to use the one piece adapter on the steel motor.
In the mean time Ill run the fisho leg and 2 piece.
Im thinking a Pan plate with no dump holes in it but just a small barbed hose fitting through the plate into the one piece and a hose that goes out through the case maybe with a flow regulator on it.
The entire one piece dump cavity with drain holes blocked could then become a poppet cavity with just one poppet drain .(dry Stacked)
The water pump could be cooled directly from a lower water feed tube, maybe 1/8 jet in through the lower case.
Looks like Ill have to either pull my power head off again to measure the pan (cowl plate) up so I can create a .dxf file to laser cut a modified one or try and borrow a plate to measure up. (big job)
Ill measure up the gaskets in that area as well and get them CNC cut here as well.
Its a bloody long way to get stuff from the States and Im learning real fast that boat shops dont really want to deal in parts for 20yr old Pro Max's.

Note
When a pinion gauge like this is used you will find out real easy if your box is bent as the shaft will bind.

NZ Sidewinder
07-28-2021, 05:31 AM
Today I had a win
I bid on an Optimax Lower unit with a 25inch 13 tooth top spline.
I bid 400 buck thinking it might contain some usable parts but then again it might be junk.
I was the only bidder and won the on line auction.
The unit arrived today and it turned out to be a mint V6 lower full of good condition parts.
Just a C4 but ill put a 3.0L carrier in it and add a cone etc.
I have 4 now.

NZ Sidewinder
08-08-2021, 01:59 AM
This beauty arrived today and next job is to design a workable way of running it with stats and a poppet.
I do have a plan.491547
Its mounted on modified fishing bracket with two pin trim.

NZ Sidewinder
08-16-2021, 12:59 AM
Today I got a few new bearings to use and also made a seal retainer .
These 3.0L carriers come with threaded holes in two opposite webs.
They look like 3/16 fine ?
They look ridiculously small for pulling with so I reckon they must be there for a seal retainer.491919491920

Today I also spoke with my gasket maker and he reckons I could use 1.5mm (.060inch) graphite paper reinforced with stainless steel mesh.
He reckons his CNC cutters will cut it easy so thats really cool.
He will cut a Cowl pan pattern and some powerhead gaskets from .3mm paper as a trial for me to test then do the real thing.
The pan plate will be cut from 304 ss.

NZ Sidewinder
08-19-2021, 08:20 PM
Ive been testing propshafts for straightness and had some surprises.
One that wasn't a surprise was an Alpha shaft that I got out of a damaged complete unit that hit a rock.
Its shaft was bent .010 through the carrier bearing which is more or less the mid point.
The other 3 were outboard shafts and all were within .0005 at the Carrier bearing journal but the surprise was that the prop spline shafts of two of them were way out of concentric with the fat part at the thrust washer shoulder position
One was .0045 inch, one was .0012 and the good one was .0005.
This is strange in that between centers the bearing journals are fine but the prop shafts are not straight.
Is this typical?
Also found that the gear select pin that goes inside the propshaft was different in the big bearing case.
It has a double length pin with a spring inside as well as double indent plugs and double retainer springs on the dog clutch.
I dropped an indent ball from another shaft on the floor and while looking for it found an old 2 piece exhaust plate gasket hiding under the bench so spent a morning during lockdown drawing it up in CAD for CNC cutting.
These ones are very complex to draw and that edge shaping is a real headache492080492081.

Update
I put the worst shaft back on the jig to try and get to the bottom of the issues.
The prop spline and thread dial up fine (.0015) so its just the prop spline shaft itself thats not concentric.
The spline and thread are machined true to the fat part.
This means that this shaft and others like it are out of balance but I doubt that it matters much.

NZ Sidewinder
08-25-2021, 09:55 PM
I put a coat of 1k primer on it to look for defects and I'll sand it off and it doesn't look too bad.
Lots of time in this box and another to do yet.
Can't have too many of them.492295

LakeFever
08-26-2021, 07:25 AM
Impressive piece, your a dedicated man

NZ Sidewinder
08-26-2021, 04:18 PM
Thanks.
Next one will have the same terminator type stainless steel skeleton but I'll try and pick up the water from the very lowest part of the underside of the bullet.
The removable bullet tip will remain as a pickup option though.
Those bullet tips are dead easy to make .
I just cast a cylinder of epoxy in a lid from aerosol can with the wall extended a little with aluminium tape.
This one has a 10mm thread tapped deep into the casting but will try casting the thread next time
The feed holes are drilled while the epoxy is still in the mold and the profile and locating shoulder are created by spinning the casting on a stud in the tapped center hole.
I spin it in a battery drill while shaping it with a 36 grit sanding disc on a 5 inch angle grinder.
Very easy and fun job.

NZ Sidewinder
08-29-2021, 03:03 AM
Started another lower unit today.
It takes about 2 hours to fold up and weld the spine water duct.
This one will take a fraction of the time that the last one took.
I found a mint set of non ratcheting gears for it but will investigate whether I can use a ratcheting clutch with those gears.
The drive shaft I'm going to use has a 13 tooth top spline so that needs to come off and be replaced.492422492423
The weather is warming up now so I'll be able to get back to the hull.
We are currently in a lock down which is a boat builders paradise.

NZ Sidewinder
08-30-2021, 04:10 AM
Today's work.
This low water pickup is slightly different than the last one.
Its lower and larger, hopefully not too large and hopefully the water flow wont eddie in a turn.
492470492471492472
The bullet nose shown is just a wooden dummy and not the correct profile.
Importantly that little stainless inlet duct behind the bullet point will get a small stainless flange tomorrow so that
The polyester filler can go behind the flange so that there isnt a join in materials that high pressure water can penetrate and possibly de laminate.
That point screws on and off so I can revert to a conventional bullet point water intake if this one doesn't work.
Overall this lower will be 3/8 inch longer than the one in post #53

In case anyone is wondering how I get that threaded rod straight and true to the center line of the case, I have a mandrel that slides down the inside of the case into the gear selector journal.
A 8.5mm long drill fits through the mandrel and drills from inside to outside.
Then the tap goes from the inside out ways as well.
The thread is sealed with Locktite 577 and a nut.
Later on in the process the unit is held at an angle in a vice so that poured epoxy creates a 45 deg ramp that defects water from the horizontal to the vertical and this epoxy buries the lock nut on the thread.


IMO Mercs that work hard should also look hard and for this reason I dont really like the Alien Cowls so today I brought a complete cowl setup to restore.
Ill set it up to fit my Pro Max and overall with the offshore leg and make believe sporty lower it will at least look like a race Merc492473

NZ Sidewinder
08-30-2021, 10:36 PM
The skeleton is almost done now.
Just the 1/2 inch socket to be fitted for outfeed to the pump.
This nose is a dummy wooden one.
I sandblast the stainless then use polyester Auto filler as a butter layer then epoxy over the poly.
This works well on the Aluminium also.
We get out of lockdown tomorrow so Ill be able to pick up a few bits and pieces to finish it.


Ive found that polyester Bog has much better adhesion to prepped Aluminium than Epoxy does.492553492554492555
The poly bog I use has the glass reinforcing in it.

Ill probably add a stainless vertical jail bar to that intake throat.

NZ Sidewinder
09-04-2021, 02:41 AM
Here is that skeleton with some flesh on it.
This one is slightly different to the original in the background.
It has a more aggressive and lower water pickup and is slightly finer in shape.
It will get one top layer of Epoxy cloth over the walls of the Gearbox and carrier case and also an epoxy cloth layer from the leading edge of the crescent back to the trailing edge.
These are cheap and easy units in the context of something to do over lock down but in the real world they dont really stack up price wise.

492760

NZ Sidewinder
09-04-2021, 08:47 PM
Lol yes and now I have an offshore leg to use I need to make another one as that one is for a Promax on a fishing leg.
The obvious option is to build another motor around those wings and alien cowl.
Before I became obsessed with lower units I had a fetish for 20inch midsections so have a few.
It may get real interesting when I start on powerheads.

I have this nagging desire to put an SR20det or a Honda K series on a midsection.
These are legendary 4 cylinder 4 strokes that can go Hi po for coffee money.

NZ Sidewinder
09-08-2021, 03:07 AM
Water pump cooling is sorted.
The water pump sits in a pocket that is probably feed water from that 3mm hole in the pump base but its difficult to ascertain just how much water is flowing so today I took all the guesswork out of the matter and provided the pump cavity with ****e loads of water volume.
I also added some other points to steal water from if need be.
492898

NZ Sidewinder
09-10-2021, 03:43 AM
Today a lower unit arrived that Id purchased on line as a water in oil write off.
It was a 2015 150hp 4 stroke EFI 25 inch in mint condition.
100 bucks.

Thought there might be something salvageable inside that I could use somehow.
The drive shaft is very similar to a 2.5 in many ways although it has two bearings plus the pinion bearing.
The main driveshaft taper bearing has the same cone diameter (2.250) but a smaller shaft size through the ID (1 inch?) yet to measure properly.
The second taper roller is irrelevant really, and pinion bearing and pinion spline etc are the same so its likely I can shorten it and change the top bearing so as to have a good drive shaft for a 2.5L.
I dont know anything about sport masters but it may fit one of them dunno.
The carrier can be machined to fit a 2.5 and it has the oil drain. dont really want to machine it though.
Gears are big and strong looking, 1.92:1.
Prop shaft is no good.
Carrier bearing journal is rust pitted.
Housing is mint.
Bullet diameter is 1/8 larger than a 2.5L
May just lookout for a new prop shaft for it for a rainy day.493027

NZ Sidewinder
09-22-2021, 07:24 AM
Im still doing lower units, organising mid sections and generally sorting the wheat from the chaff.
Ive ordered a 200 ft lb Tollok shaft coupler and will do some work to decide whether one will hold a V6 2.5 drive shaft together.
I have no problem spigoting and welding shafts but at 120 bucks a coupler might be attractive if it works.
First test is to put a shaft together with one and dial test it for concentricity.
Some Tolloks self center and others dont.
May need to grind the 7/8 shaft to 22mm, hope not.
I know they rust so if its works it will need to be painted.


Remember the days when we played with small block Chevs and wanted to put 2 inch headers on those old cast iron heads but the bolt pattern was too tight?
The work around was to use the standard bolt pattern and countersunk hex screws to fix an over sized mounting plate to the head and then drill and tap that plate to accept any header bolt pattern we wanted.

I built a few water jacketed header sets for jet boats like this and intend to use that same system to mount a water jacketed tuner under my one piece.

The poppet water will go into the tuner water jacket near the base and spray out the bottom near the bell lip.
This way the tuner will stay cool without putting water into the exhaust stream.

Im using a 10 mm Aluminium mounting plate with water jet cut oval ports and the base of the tuner will match that but made from stainless which is easier for me to work with.

The tuner will be fabricated from oval stainless tube that can be cut to form the slight taper etc. etc etc.
This oval tube is whats used to make high flow exhausts for very low cars
Of course it could end up in the scrap bin but may not.

Most of my money comes from something I invented by pursuing outrageous engineering ideas, although there is no denying that through the years I have generated a substantial volume of expensive scrap.
However you only need to get it right once or twice to make it all worth it.

LakeFever
09-22-2021, 08:27 AM
Im still doing lower units, organising mid sections and generally sorting the wheat from the chaff.
Ive ordered a 200 ft lb Tollok shaft coupler and will do some work to decide whether one will hold a V6 2.5 drive shaft together.
I have no problem spigoting and welding shafts but at 120 bucks a coupler might be attractive if it works.
First test is to put a shaft together with one and dial test it for concentricity.
Some Tolloks self center and others dont.
May need to grind the 7/8 shaft to 22mm, hope not.
I know they rust so if its works it will need to be painted.


Remember the days when we played with small block Chevs and wanted to put 2 inch headers on those old cast iron heads but the bolt pattern was too tight?
The work around was to use the standard bolt pattern and countersunk hex screws to fix an over sized mounting plate to the head and then drill and tap that plate to accept any header bolt pattern we wanted.

I built a few water jacketed header sets for jet boats like this and intend to use that same system to mount a water jacketed tuner under my one piece.

The poppet water will go into the tuner water jacket near the base and spray out the bottom near the bell lip.
This way the tuner will stay cool without putting water into the exhaust stream.

Im using a 10 mm Aluminium mounting plate with water jet cut oval ports and the base of the tuner will match that but made from stainless which is easier for me to work with.

The tuner will be fabricated from oval stainless tube that can be cut to form the slight taper etc. etc etc.
This oval tube is whats used to make high flow exhausts for very low cars
Of course it could end up in the scrap bin but may not.

Most of my money comes from something I invented by pursuing outrageous engineering ideas, although there is no denying that through the years I have generated a substantial volume of expensive scrap.
However you only need to get it right once or twice to make it all worth it.


LOL your making me feel old. To the second comment, that is a signature worthy statement

tnelsmn
09-22-2021, 07:58 PM
Hats off to you for the amount of engineering and work that is going into this. Fun to follow along and see how others think of solutions to problems.

NZ Sidewinder
09-27-2021, 04:42 AM
Today between other jobs I built a poppet wall in my one piece.
There's a lot of discussion about adding poppet galleries to one piece adapters and Ive only done it to support the pan plate and gasket.
My poppet dump to atmosphere is through a water jacketed tuner piped from holes in the floor of that large dump cavity.
For this reason the poppet gallery wall has holes in it as the water doesn't go out the bottom of the gallery as with a normal poppet dump but instead through the new wall into the dump cavity which is now almost completely sealed off from the pressure side of the cooling water system .
That wall is bolted in place not welded so it can be deleted if necessary but probably more importantly I didnt want to weld my nice one piece.
The hole Ive drilled in the side of the adapter plate for the bolt that pulls the wall snug into the corner could be plugged later if need be.
The photo of the Pan with the Aluminium tape over the dump holes is just a mock up since I haven't got my dumpless Pan plates back from the water jet cutter yet.
493604493605493606493607
The reason Im doing this to a one piece and not just using a 2 piece is that Im only running a 7k motor and want stats and poppet but I want the strength of an offshore leg and mounts.
I tend to be very hard on gear.

NZ Sidewinder
10-02-2021, 03:40 AM
It's been a good week overall although I'm not getting much traction on my build.
I'm waiting for water jet cutting and the weather isn't good enough yet to get back onto hull work.


However this week has been very productive with regard learning about the merc outboard.
I purchased a 25 inch 3.0L midsection on line for one dollar.
The idea was that I'd use it to practice cutting down to a 20 inch.
Little did I know that the 3.0L uses the same transom clamp as the 2.5 except for the lower mount yoke.
This midsection had a mint clamp and the yoke came off by hand and a 2.5L one went on to produce a really nice base for a new build.

I'll put guides in the trim rod holes to hold the clamp true at high speeds.
This bit of kit was a major score for one dollar.
Then came the job of looking at how to cut and weld the leg which was the reason I purchased it in the first place.

Looking at the leg it became apparent that the casting that produced the 25 inch was almost an extrusion of the 20 inch and the the stud thickening in the 25 inch casting extended back into the casting to where the 20 inch leg studs would have been threaded.
In simple terms the 25 inch leg could have 4.5 inches cut out of it and have new stud holes tapped in it to become a 20 inch without any structural welding required.
An astonishing outcome.

It so happens that a near new 1.92:1 150hp 4 stroke gearbox I got for 100 bucks will bolt up to it.
So for 101 dollars I have the beginnings of a poor man's XS.
Just kidding around of course, maybe
One day I'll sit an LS1 on it and go kick some 450R ass.

The next revelation was that the difference between a two piece 225 ProMax adapter plate and a 175hp stock one is about 1 tablespoon of Aluminium which can be carved out and finished nicely with a rotary burr in less than an hour.
Its only the port size in the top of the top plate that is different.

493779493780493782

All a bit of fun and something to do.
This took just a couple of hours

NZ Sidewinder
10-03-2021, 01:40 AM
Its even simpler than I first thought.


The leg now is 19 inches.
One cut through the leg at about the 19 1/4 inch mark then put it in a Mill to be skimmed off at 19 inches.
Possibly in practice its best to rough cut at 19 1/4 inch then trim down to 19 1/8 inch by hand power tool then mill the last 1/8 inch.
Then either by measurement or in my case by template mark, drill and tap the bolt and stud holes.
there are various tricky ways to mark and drill the hole for the snout locator dowel.
The exhaust liner is above and out of the way but I may delete that and run an offshore system.
Cone that lower and fill it back up with its internals which are big and heavy.
Then put it in the corner out of the way for now.

Its now at the machine shop and will be bolted to a face plate and turned in a lathe as it is too tall for the mill.
493797

NZ Sidewinder
10-08-2021, 04:05 AM
So I have two concurrent projects on now.
First is the 2.5L Promax sidewinder and second a 19 inch 3.0L build.
Totally unrelated for now at least.
My 2.5L project has first priority and the conversion or modification of a one piece adapter to suit the steel Pro max has taken some thought.
Basically Ive sorted what Ill run with and am now building it.
The principle is that of a 2 piece, more or less.

The poppet and stats are retained, the poppet dump is fed into the one piece through a pan plate that has no dump holes.
So the large dump cavity of the one piece is now a poppet gallery that feeds the tuner.
However there is the issue of air being trapped in this large gallery and also a possible issue of the poppet flow being restricted by the long journey to the tuner so to fix both these issues with a single fix Ive added stand pipes to the gallery that extend almost to the roof of the gallery.
This pair of stand pipes drains air and overflow water directly to the mid section and ensures that there is a continuous head of water feeding the tuner jacket.

This system ensures that the poppet flow is never restricted and air never accumulates in the poppet out feed gallery.

The water drains to the tuner via a pair of 1/2 inch tubes that meet a pair of female sliding fit sockets.
This means there are no threaded couplings in the line and the tuner can be removed easily.
Probably the most significant realization so far in designing this system is the need for a way of draining/venting the air from the dump gallery. Hence the two stand pipes/overflow pipes ( short pipes that almost reach up to the pan plate)

494365494366

Tonight I tacked up an oval tuner tube
1l2 inch taper over 9 inches.
A 6x5 inch Ali plate 1/2 inch thick will be attached to the tuner bolt pattern with countersunk Machine screws and then the tuner will be built on a 6x 5 inch x 1/4 inch stainless base plate that will bolt down to that Ali plate.
The tuner pipes and water box will weld to this stainless base.
Ive had a few thoughts about cooling the tuner etc.
Im thinking that putting water into the exhaust stream could change the balance of the exhaust system so will avoid it, opting instead for a jacketed tuner.
The motor really needs to be 280hp just to to carry this lot.
494367494406494407

Then the fun stuff.
The 25inch 3.0L leg I hacked in half went in the lathe today.
My brother did the work.
Ended up at 18.700 inch long.
He first built a face plate with a center spindle that reached right through the leg and a neat fit out the water tube hole.
This spindle was supported by the tail stock live center.
Worked well and if it hadnt been for this center spindle the leg would have certainly flowen out of the lathe when he accidentally started the lathe when set on 1000rpm.
He estimates it got to 300rpm before he could get on the brake.
however all's well that ends swell.
494368494369



494408Time now to start looking over the fence at the Hull
This sketch is the plan and its too far along to turn back.
It should produce a low CoG boat
Deadrise 20 deg.

LakeFever
10-08-2021, 06:21 AM
Excellent work!

NZ Sidewinder
10-12-2021, 03:29 AM
Ive got two lowers being painted in Epoxy Black Gloss and had a peek today.
Very impressed.
I had planned to have then finished in some outlandish color but in the end decided to go Black.

494569


I may get a one piece done in red or blue.
These two lowers will get white or gold bullet points which should make a nice contrast.

NZ Sidewinder
10-13-2021, 02:41 AM
Today my laser cut pan plates and water/laser cut tuner flanges arrived.
The Pan was pleasing because it fitted well and all the bolt holes lined up
Note the missing Dump holes.494613

494614
The plate on the right is 1/2 inch Ali and bolts to the adapter tuner bolt pattern with Counter sunk Screws
Then the tuner with its 1/4 inch base plate bolts to the Ali plate.
Some of these bolts are tapped into the Ali and some bolt through.

NZ Sidewinder
10-17-2021, 03:01 AM
Tuner mostly done now.
Water from the poppet fills the jacket from the side and the water exits the tuner jacket from the top near the base flange.
There is a 3/16 drain in the bottom of the jacket.
Its all port matched but I doubt that will make much difference at 7k

I used a handy system to mark out the flange plate to match adapter thread pattern.
I made up 8 5/16 unc pointed studs which were screwed into the holes all at the same height.
The Flange was carefully clamped over the pointed studs then hit with a soft hammer.
Perfect set out.494848494849494850494851

NZ Sidewinder
10-21-2021, 04:39 AM
Today I ordered two full sets of New Zealand made studs for the power head/ plate and for the lower unit.
Power head ones made from 4140 zinc plated and lower unit from 316.
560 bucks, almost fell over.

NZ Sidewinder
10-28-2021, 07:36 PM
Engine almost done
One unit has a single low pickup and the other has 3 holes at 8mm dia.
May put a 4th one in there yet.
Both bullet points are cast epoxy with lots of CSM mixed in.
I made about 6 of them and smashed them on the anvil with a hammer.
Thay are very tough
Epoxy doesn't like being cast in a lump but even although it did tend to heat up it's still really tough with the glass mixed in.

495553495554

LakeFever
10-29-2021, 06:03 AM
For a guy who claims to not like sanding, that is some stellar fairing. Very straight and clean

NZ Sidewinder
10-29-2021, 02:03 PM
Lol,
Epoxy, the 10th wonder of the world.
Right after compounding interest and fractional Reserve Banking.

NZ Sidewinder
11-07-2021, 06:24 AM
Adapter is done and the back on the leg now.
Water is tube stainless and has a locator ring welded to it that locks under the keeper at the adapter plate.
The jacketed tuner has a stand pipe at rear which ensures that there is water in contact with the base plate for more cooling.
There is also another small vent hole at front of tuner at very top to also help keep the cooling water in contact with the base.

The pan plate has no dump holes and a small drain into the water tube .
Overall this one piece works the same as a 2 piece, however in this case the poppet discharge goes to the leg via the tuner jacket.496039496040

NZ Sidewinder
11-19-2021, 04:21 AM
The reassembly is done and the motor is going up the road to a Mechanics place for some work.
Oil gear is coming off then a general check, possible take the heads off for a look and the motor will be run up etc.
Put it on the scales today and the leg + power head weighed 161kg and the lower unit 23kgs
In American lingo thats a total of about 404lb.

The Jack plate got some much needed mods also
Its got a doubler plate each side with lugs that take the vertical load off the transom bolts and holes, and lower lugs that carry the vertical load of the jackplate.
This means that the transom bolts only provide clamping force and are not vertically loaded.
As I mentioned earlier Im hard on gear.496674

496675
My young Fella has just finished school so Ive got cheap labor for a month or two.
Here he is bolting up the motor to a makeshift stand for transporting.
By some miracle we got the clamp hole pattern to line up first attempt.

spybot
11-19-2021, 06:01 AM
Can you explain more of the jackplate mods
They have gone straight over my head sorry

NZ Sidewinder
11-19-2021, 02:12 PM
Can you explain more of the jackplate mods
They have gone straight over my head sorry

In the case of this particular jack plate it came off a 3.0L Merc/ bullet hull that had seen some regular rough water use.
Because of this the transom bolt holes in the jack plate mounting face, ( the face of the heavy Aluminium Angle sections) had worn oval(slotted).
It most likely that the fiberglass transom was soft and the bolts loosened allowing the engine and jack plate to slam up and down.

My fix was to lay 4x1/2 inch flat section Ali plates over the the top of the standard angle sections but make them longer at the upper and lower ends.
These plates are now what bolts against the transom.

Because these plates are longer at the top they extend above the top edge of the transom and this allows for a heavy angle section to be bolted on to form a lug that rests on top of the transom.
This means that the jack plate can hang on the transom without any transom bolts.
Not that you would do that.

The at the lower end of these long plates is a block of Ali plate that forms a 1/2inch lip that Carry's the weigh and shear loads of the jack plate so that none of the transom bolts or any of those countersunk hex screws take any vertical shear forces, other than the ones securing the upper and lower support blocks.
I'll add a cross section sketch after breakfast.
Green is the Mod
496700

NZ Sidewinder
11-21-2021, 04:08 AM
Today I decided that the mechanic was too busy and chances are Id drop the motor off there and not see it for a while so decided to kick it in the guts myself, which I did and it snarled at me.
It idled at a steady 140 deg F at the stat tell tale.

I need a pump dummy shaft kit so will leave the injection on for now.
Today for first start up I ran premix plus the injection.
Its a scary beast and with the dry tuner it has a harsh note.

LakeFever
11-21-2021, 07:30 AM
Congrats! First fire is always a fun day. I hope we get to see and hear this beast under power one day. Truly a one of a kind build

NZ Sidewinder
11-22-2021, 02:07 AM
Thanks
Ive worked with many different types of machines in my time but outboards would be the biggest vacuums of time ever conceived.
However its more or less done and today I ordered some rats and mice needed to finish the spare lower unit for it.
Also contacted Brucato about an ACU.
So now its back to the hull, the second biggest Vacuums of time ever conceived.
But there is one issue yet to be addressed with the motor and thats Pyros.
My one piece adapter has a pair of 1/8 pipe threaded holes tapped into the exhaust ports so these might be the perfect place for them.
Ive run pyros on diesels before and from memory they were 1/8 npt and 1/8 probe diameter.
On a Diesel these skinny probes can snap off and go through the Turbo but that's not applicable on an outboard.
On the Hull Im going to cut the new transom down from 25 to 20 inch.
The 25 inch seemed like a good idea at the time.

Ive got a heap of stainless embedded threads to epoxy into the Pad to secure the 1/8 galv steel pad runner.
These are made from 30mm long pieces of 16mm (5/8) s/s threaded bar with M10 tread tapped through them.
These anchor into the pad and allow counter sunk screws to hold the Pad runner.
Some will fit into the transom also.
These ones will hold the braces for the Pad /wing extension aft of the transom.

Haven't decided whether to make the boat a left hand drive or center steer.

The 225hp will start out on this current hull but it will probably end up on an offshore boat Im planning.
But thats another story.

LakeFever
11-22-2021, 06:03 AM
I can relate on many levels. It takes what it takes, it’s not done until it’s done and if it was easy everyone would do it. Those three remarks are frequently voiced on my projects. In the end we have never regretted building things “too good” but in the early years there was plenty of frustrations from not building things good enough.

reminds me of an old saying “the sweetness of low price is forgotten long after the bitterness of poor quality remains” I don’t know who said this but there was an old magazine cut out of this hanging in my fathers work shop.

NZ Sidewinder
11-24-2021, 04:41 AM
Here is a milestone Photo of my engine and also a photo of my young fella in his new Clubman class race boat.
Its a 30hp class that we are getting into
The Hull is open, Vees, flatties, tunnels, anything
The motors are std 2 cylinder 30hp or 3 cylinder 25hp, standard midsection, coned lowers with Low water pickups allowed.
This one with a 19 inch prop gets along at 45MPH gps and has a 21 inch prop for lighter drivers.
As a kid id see these boats racing on the lake and dreamed of having one.
A lifetime later I got one.
496892
496893496894

tnelsmn
11-26-2021, 12:09 PM
Sure is pretty ProMax!

NZ Sidewinder
11-26-2021, 01:27 PM
Sure is pretty ProMax!

Damn, id rather have one that looked like it would tear your arm off if touched.

NZ Sidewinder
02-05-2022, 11:43 PM
I got sidetracked by another project that was suppose to be a weekend job.
Spent a few months on it.
It's a Cyclone rx1950 gen3 it think.
Almost done.
Australian boat used for skiing and ski racing through the 80s and 90s.
Probably faster than my sidewinder but not a boat I'd push hard in a big sea.
I'm almost ready to get back onto the sidewinder project and really looking forward to it

500745500746500747
Havent had much seat time in this boat but already know which boat id rather be driving heading into a hole shot buoy at 70mph
Id rather be in a Tank of a Sidewinder.

NZ Sidewinder
03-31-2022, 02:04 AM
Ive been busy racing my mini boat and trying to persuade my 19ft 6 Cyclone 225hp not to kill me but am managing to make some progress on the sidewinder.
The bottom is coming true now and a few more days will see it ready for an epoxy skim coat.
Its 250lbs overweight so Ive decided to make her a single seat center steer.
Boom that's 220lb shaved off the weight so we are back in the race.
Haven't decided whether to put a 2.5 200hp on it and circuit race in a restricted class or go 250hp 3.0L unrestricted on my 18.7 inch 3L mid section.

Circuit racing the 30hp mini boats is a lot of fun.
Its mostly kids and they are ruthless competitors.
Typically the start boat will gather us all up from where we are milling and in a sweeping turn have us assemble abeam of him in our pole positions as he runs us down the straight toward the start finish buoy.
The deal is that we are supposed to maintain our pole position lines around the first two Buoys but juniors make their own rules .
For them its just like a motocross hole shot, Chaos.
Im 200lbs fully suited up and doing 45mph.
Most of them are 90lbs and doing near 50mph so I usually get to watch the races from the rear although occasionally Ill sneak through the inside and manage to block most of them for a place.
Im running a 30hp Parsun with a 21 inch 3 blade with the propshaft at pad level at about 5750 rpm.
45mph is over 20% slip so I probably could do better.

NZ Sidewinder
04-02-2022, 02:07 AM
503175503176

Slowly but surely she is straightening out.
The strakes are becoming sharp and straight rather than wobbly and rounded.
Some of the Hooks are the result of the bare skin rebuild but there are also plenty of production hooks in the Mold.
Im really looking forward to racing this boat but will warn the other drivers that it's likely to leave very deep holes around the Buoys.

NZ Sidewinder
04-28-2022, 05:23 AM
Id say the Sidewinder has lost her 225hp but I have a 200hp 2.4L for her.
Here is a Photo of the 225 Pro Max racing.
She is good for 80mph but best thing about that boat is it corners like its on rails.
Note the starboard Pee tell tale.
Its reassuring to start the motor as see that.
The cooling system as set out in earlier posts seems to work well although I have had some concerns about low temps at WOT.
Each cylinder head has a temp prob up top ant the engine will idle at 140degF but slowly drop toward 100F at speed then raise again to 140F once back at low speed.
Water pressure at WOT is around 25psi.
Ive scratched my head a lot over this as I cannot see how my One piece with its mods can behave any differently than a 2 piece plate as it is basically a 2 piece.
Ive come to the conclusion that these temps are normal so I just give it death.
6500rpm is what it races at.
I have blocked one of the 3 low water pick up holes though as I dont think 25psi is necessary.
each hole is 5/16 and there are now 2.
Ive removed the warning beeper from the remote and put it in a cavity above the dash where it sounds very loud and also have two red blue flashing warning lights.
Ive also realised that the offshore leg adds low down weight (Ballast) and when the big fat Alien cowl is off its obvious there isnt really as much weight up top as can appear compared to whats hanging from the clamp down.
Propshaft is 2 1/4 below pad which is where these boats like it.
I could raise it but cornering would probably suffer.
This boat races in a class of 300hp boats which lose ground to me in the turns so its an advantage im keen to retain.


504244

NZ Sidewinder
07-10-2022, 04:27 AM
I've decided to use a 3.0L on this boat and have been building a midsection for a while.
She is heavy and 225 or 250hp will be required.
This lower is from a 4 stroke and runs 1.92 gears which is a bit low but it will do for a start.
I'll put a short drive shaft in it the same length as an Alpha but with double bearings, and use a coupler.

The midsection is 18.700 inch and was to have an offshore type snout added, but I've changed my mind on that.
It would require me to drill holes in the trunk, and that is probably not wise, so it will exhaust through the bullet.
507117507118507119507120507121507122
The 3.0L engine is now an attractive option in NZ where 2.5stuff is really sort after.

NZ Sidewinder
09-19-2022, 03:54 AM
Changed my mind and she's getting a 2.5L
A 1991 2.5 turned up at my place begging to be rebuilt.
Boats now510179510180 ready for bottom paint

NZ Sidewinder
09-20-2022, 04:28 AM
Today was a good day.
This 2.5L 200 is a1991 f block, and I pulled all the liners out because two were buggered and they were all exhaust slotted.
I also pulled all the rusty old liners out of an old block that's been laying around here for ages.
I cleaned them up and measured the ports.
Something just didn't add up.
They were high, and the two smaller boost ports were wide.
Then I went out to the scrap heap and retrieved the block for a closer look, and sure enough, the exhaust chest was like a promax one and buried under the paint was ff.
I hauled it inside and sat the f front half on the pins and it dropped home mint.
I'll put a crank in it and blue the dowells to see what the fit is actually like, but by hook or by crook, those two halves are going together.

Then as if by magic, these +.020 1991 Pistons showed up.
Na not really magic, I figured I'd need either a set of std or plus twenties so got a set of each.
These days I often buy two sets of everything as my biggest fear is lack of supply.


510226

NZ Sidewinder
09-21-2022, 05:12 AM
This is my first try at chest porting.
Took 2 hours.
There is a lot of work at the exit port and I reckon a bloke could easy come unstuck there.
I've left some meat there because there is a spot where it could get real thin.510355510356

LakeFever
09-21-2022, 06:02 AM
It does get thin on the inside of the dump. I did the same to my block and two piece plate. I thought about using jb-weld on the backside of the dump on the block and the plate to beef it up. Was thinking clamp a flat plate over wet jb with parchment paper and then use right stuff to seal it during assembly. Now im thinking the promarine reinforced base gasket with some right stuff might be enough on its own.

NZ Sidewinder
09-21-2022, 03:09 PM
I erred on the side of caution and left that ramp out of number 5 thicker over the hump, (steeper) and then sloped it down to the exit port full size.
In effect, sacrificing some cross-section size.
I'd say the floor of the chest at that thin point is now around 3/16 - 7/32
Then, the next issue was the rim size of the actual port.
I put an accurate pan plate on the block and scribed it then made sure that I didn't cross that line.
The base gaskets from memory are a little concerning.
I get some 2.5L gaskets cnc cut but that one isn't able to be copied because of the reinforcing in it.
I have made the .dxf file to have one Lazer cut though and could make that bit wider.
A painted or coated copper gasket might work.

LakeFever
09-22-2022, 05:15 AM
I did the same i scribed to the baseplate and did not go further. I considered spray copper gasket as well. The base gasket i have is a nice unit it’s reinforced with steel sandwiched in the middle. Promarine part number 2693A

NZ Sidewinder
09-30-2022, 03:15 AM
To circuit race this boat within the rules I need to cancel out the step.
So I'm bolting in a delta vee plug
I've epoxy embedded 5/8 unc anchors that have 3/8 unc internal threads for bolts to thread into.
These will hold whatever pad system I want to use.

Also picked up a Spinilli prop, a long way from home.
The Spinilli came from Australia and was used on a 300hp small shaft race Merc of some kind for ski racing

I was perplexed when I got it as the thrust washer end doesn't appear to be machined at all.
Also the bore at the front end was 1.062.
With regard the rough cast thrust surface I blued and lightly lapped it against a chrome thrust washer and it showed a nice 3 point contact which was a surprise.
The 1.062 bore was a concern so I made a 35 thou wall thicknes bush for it, which works well.
To run it on the surface, just relying on the nut to hold the prop firm against the thrust washer and therefor true, would be a big ask IMO.
probably asking for a snapped shaft?



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NZ Sidewinder
04-08-2023, 09:20 PM
I been really busy saving the world guys and doing some other important boat stuff but haven't abandoned the Sidewinder.
Today she got a coat of epoxy undercoat.517571517572517573517574517575
Here are some pics of what I've been up to.
That's an unraced 15 inch nitro stinger.
Doing up a 15 nitro Hustler as well.
Been racing a 225 promax a bit and winning here and there.
They are a mighty motor, too good to race.