HST Here I come.

[dompie99]

Good week to all,

I was wondering If I was day-dreaming or what.

Yesterday, I was trying to ''push'' on this new rebuilt V6 3.0L slightly above the 3500rpm ''physical limit imposed by the break-inperiod since it's already 12hrs past this time ',already.

I noticed a Strange feeling since I am new to HST's.

At about 4200 to 4300 rpm, the boat started to ''glide'' and even though the RPM was constant, the speed jumped from 42 mph to 65 mph in a peculiar way, you could feel the boat ''airborn'' andfeel a little more the little chops of the lake.

I believe that is the way a Tunnel is behaving ??

I pushed it to about 5000 rpm with a 28'' chopper and I made it to about 80 mph ( !!??!!?? ), at which I felt a little chinewalking, there is still a little air in the steering hydraulic system which I will eliminate during this week.

FINALLY, I am getting close to my objective and reach the 100 mark.

Couldn't done it without you guys.

[wired247]

Kudo's. I have no idea how you could stay under 3500 for 12 hours. 12 hours is a HUGE amount of time on a boat going slow.

[crankbearing]

Because I told him too - I was not putting anymore sleeves in that block. LOL.

[BeefKid]

yes you are feeling the boat "pop" and some say it starts packing air...

[dompie99]

Because I told him too - I was not putting anymore sleeves in that block. LOL.

Yeahhhh right

[dompie99]

I am sooo scared about my Machinist, He menaced me not replacing new sleeves into it if I blow it once more.

[crankbearing]

I see a merc re-man powerhead in your future! . Actually Jacques, you stayed with it and worked through the hassles with jetting etc and good on ya to start getting it tweaked now. I know how you feel, I got the 250xs all rebuilt sent out 2 sets of fuel rails with spare injectors grey air and fuel, out and got them back the high pressure tap was leaking at the o-rings, one fuel injector leaking had to replace the (if) NEW pinched o-ring, one air GREY injector is completely DEAD so after spending 300$ US for a cleaning and calibration plus UPS both ways and they sent back my 2nd set of rails but not my spare injectors. I should have just ordered a new set of rails; now I have to anyway for peace of mind.

[at100plus]

Something is wrong or there is quite a bit of air in the steering if an HST is chine walking at 80. Do you have solid mounts? What is your engine height (specifically the lower unit bullet relative to the bottom center pod)?

[dompie99]

That's what I was thinking a while after I posted this thread. I went to check it this afternoon AND there is quite a ''loose end'' of about 1/2'' of ',end play'' on the cylinder end.

I have solid mounts, and the prop shaft is at about 3 to 4'' below pad (center pod). That's why I keep there for a couple hours still, I don't want to get My machinist '' ANGRY '' at me and refuse systematicaly to replace another sleeve on this bloc (lolllllllllllllllllllllllllllllll )


The prop is a Chopper 28''

[dompie99]

I see a merc re-man powerhead in your future! . Actually Jacques, you stayed with it and worked through the hassles with jetting etc and good on ya to start getting it tweaked now. I know how you feel, I got the 250xs all rebuilt sent out 2 sets of fuel rails with spare injectors grey air and fuel, out and got them back the high pressure tap was leaking at the o-rings, one fuel injector leaking had to replace the (if) NEW pinched o-ring, one air GREY injector is completely DEAD so after spending 300$ US for a cleaning and calibration plus UPS both ways and they sent back my 2nd set of rails but not my spare injectors. I should have just ordered a new set of rails; now I have to anyway for peace of mind.

I strongly believe that your crystall ball is not so far from truth my man. My girlfriend will kill me, if I do but heyyyyy who's the bOSS here ???.
I told her to stop yalling at me, I will get out from underneath the stove. lollllllllllllllll

[at100plus]

3-4" below the pad is waaaaaaay too much jack it up till the center of the lower unit bullet is even to 1/2" above the lowest point on the pad. I assume you have low water pickups right? With the engine that low it will handle much worse especially when you renter from being aired out. You need that steering play out too.

[dompie99]

This ''set-up'' was meant to be used in the ''break-in '' period only.

Before I installed the Setback plate ass'y, with 4', of set-back, the jackplate was way too high, Just to explain, at the lowest position, the bullet was 1'' above center, and all I was capable to was getting the engine out.

Now The ending point of the jackplate travel is 1 1/2'' below pad.

I will try this when I receive the Cleaver Prop. (34) soon.

[at100plus]

This ''set-up'' was meant to be used in the ''break-in '' period only.

Before I installed the Setback plate ass'y, with 4', of set-back, the jackplate was way too high, Just to explain, at the lowest position, the bullet was 1'' above center, and all I was capable to was getting the engine out.

Now The ending point of the jackplate travel is 1 1/2'' below pad.

I will try this when I receive the Cleaver Prop. (34) soon.

I wouldn't run a cleaver unless you have 300+ hp. Worked DAH SRX, Chopper, Mazco, Lightning ET semi cleaver or Performance Propellers semi cleaver would be my suggestions. 4 inches of setback won't cut it either. HST need more like 15 and hydraulic jack would be best if you have the coin. Jack till you lose some water psi and bump it down. That hull should be extremely stabil at 90 mph. I don't think I ever ran mine anything but wide open when I had it. Wow can't believe that was nearly 20 yrs ago.

[dompie99]

Got the prop yesterday, And will run some light tests tomorrow.

Can I ask, as a ''green'' why you wouldn't run a Cleaver with less than 300+ hp's ???

ohh by the way, there are some ''punched numbers on the prop saying 14 5/8'' X 33 in the front. Could it be that this prop was '' repitched '' ???




As for setback, I already have about 8'' so far. AT100plus, you say that more than 15'' would be better ???? wowwww. I already have the hydraulic jackplate.

[at100plus]

Got the prop yesterday, And will run some light tests tomorrow.

Can I ask, as a ''green'' why you wouldn't run a Cleaver with less than 300+ hp's ???

ohh by the way, there are some ''punched numbers on the prop saying 14 5/8'' X 33 in the front. Could it be that this prop was '' repitched '' ???




As for setback, I already have about 8'' so far. AT100plus, you say that more than 15'' would be better ???? wowwww. I already have the hydraulic jackplate.

I have found that cleavers lift the stern and you tend to throw horsepower out the rooster tail on a hydrostream if the prop isn't cupped enough anf or if you dont have enough hp to carry the bow. This is especially true on an HST which is known to need lots of hp and setback to carry the bow. 12 to 15" depending on hp and prop. You can add a solid 5-8" bracket in front of your htdraulic jack. With 225 hp you probably want a 28 pitch to see 6000 rpm. 33 cleaver will be aweful might not even plane Cleavers don't plane off well on hydrostreams either.


Never heard of 14 5/8. Put one tip against a wall and measure from the wall in to the center of the shaft hole. That will be your radius. Double that and if it's 14 5/8 then I'd say that stamp probably means yes it had been re pitched to a 33