My blown Merc XR2: 'rude guy's observations and questions

this non-running XR2 150hp came with the hull i bought. i'm in the process of swapping over one of my spare v4 crossflows, and i spent today, de-rigging it from the hull--all i have left to do is hoist it off. this boat is 18 feet and solid/heavy feeling. it will probably be underpowered by the bubbleback. so i am going to rebuild this XR2 or put a replacement powerhead on it when i get around to it.

observation: WTF is up with the hokey clamshell cowling? what a crazy rig that is. yet, i'm strangely attracted to it.
question: the spring clamps on front that close the cowl tight have a barrel nut. one of mine is missing and the part is listed as NLA on boats.net. seems like i could use a hardwood dowel or cut a off piece of delrin rod--or buy one, but what s'n'f approved vendor sells them?

observation: the telltale pee hole is very small diameter and was blocked badly in the fitting itself. are replacements available?

observation: compression was
30-110
110-105
105-0

looking forward from the rear of the boat.
question: the starboard bottom that read "0" had fine aluminum slag on the spark plug. i've never had a melted piston, (even in my racing car motors that i build myself), but is that what would have caused the slag?

observation: the "power pack" (evinrude term, don't know what merc calls them) said it was for 3 cylinders. it is on the starboard bank. but i did not find another one on the port bank. weird.

more to come as i get into either the teardown or swapping everything over to the donor powerhead.

-peter

Some here will have an old cowl clamp you can get a barrel nut off of. There got to be tons of those old cowls (stop using them in 1987/8) you can savage parts off. Just remove the hose and push or drill the obstruction in the plastic telltale hole out. The second switch box (power pack) is directly behind the other...if you remove the two screws holding the switch box you find they hold both with a spacer/standoff inbetween them. The aluminum is probably the result of the disrtuction in that occurred from either a broken part or detonation in the cylinder.

on the the next, merc-newbie question: where/how do i get the factory service manual?

-peter

e-bay

already tried ebay before i asked. looks like seloc or clymer for now. which is better?

-peter

Well Peter,

I just so happen to have a Merc service manual I bought when I picked up my 1st of 2 XR2's back in 2000 or so. Problem is, I have no idea where it is right now as I cleaned up my office and garage quite a bit before I left on "vacation" back in February. I'll ask the wife to see if she can dig it up and if so, I'll see what we can work out.

Jeff

The second switch box is behind the one your looking at.

This '86-'87 V-150 powerhead's coming off soon and after I disassemble it, I'm going to get the bores checked for taper and roundness and such, the usual stuff, so I can know whether to order standard or oversized pistons and whatever else I need.

The question is, is there any reason I need to deal with an actual marine-oriented machine shop? Or can I use one of the car-engine machine shops I'm already familiar with?

Thinking of starting a v-150 build thread, if there's any interest. BUT this will just be a stock rebuild. Not interested in a performance build for this motor.

-Peter

I'm no machinist, but the boring machine used by my machinist is purpose built so it can bore the marine blocks (to a specific depth) which have a deck at the base where the rod slot is. You can't "bore through" like in automotive applications. Guess you need to check your machine shop's capability.

well damn. that complicates things a little. i'm new to boats (been doing cars for ages), so i don't really know anyone. maybe i go to racer/al stoker? a little out of my way, but not too bad.

-peter

Good idea. Have him cut the heads and front half too, put in a good set of reeds and have some fun for a long ,long time. 2.0's and vipers are like PB&J.

Your best bet would be to take it to a marine engine shop.Out boards are bored using a old school boring bar,and need a tool bit ground to cut to the bottom of a "blind hole" Most auto engines are bored using a power hone like a sunnen ck10.They can be indexed to do an outboard it is very hard to get right.

Q & E machine in Anaheim. They do most types of outboard and watercraft stuff. My last three 2L's have come out perfect.

the rubber biscuits with the threaded studs top and bottom for the complex clamshell cowl mounting system: several of mine the metal "washer" has come unstuck from the rubber bushing/biscuit. is there fix, or do i have to shell out the $33 each for replacements. seems like re-gluing might work, but what glue?

what would you guys do? rig up a fix, or buy new ones?

-peter

e-bay or go to a newer cowl.

2 bucks each at Mcmaster

http://www.mcmaster.com/#vibration-d...mounts/=kcl9on

newercowl? are newer cowls available for these '87 2.0 liter's? who makes them?

-peter

Quote:

---

Originally Posted by pcrussell50

newercowl? are newer cowls available for these '87 2.0 liter's? who makes them?

-peter

---

He means a newer style, they don't use the rubber mounts

pete, thanks for the mcmaster carr lead. i should have thought to go with them in the first place.

back to the alternative cowls--is there a range of retrofittable years and horsepowers you can steer me to, to help with shopping?

-peter

I went form a 92' 110 V4 to a 1986 XR2 on one of my old checkmates and loved it. what a difference, all around better engine imo.

Quote:

---

Originally Posted by pcrussell50

pete, thanks for the mcmaster carr lead. i should have thought to go with them in the first place.

back to the alternative cowls--is there a range of retrofittable years and horsepowers you can steer me to, to help with shopping?

-peter

---

As you get into the later 80's they eliminated the clamshell. The newer ones have a 2 piece base with a drop on upper section. You would need some tweaking to install one (like drilling and tapping some holes in the exhaust plate), but they will work. The downside is that they are heavier than what you have. An HP type cowl is best, simple and light (but more fragile).

OK pete, you won the day with the mcmaster carr idea. three new rubber isolators, LESS than $2.00 each. they are on the motor now, and the hokey clamshell cover is fitting great. weird as it is, i think i actually _like_ it. gawd help me. am i turning "black"? :)

-peter

Just wait till you step on the gas:eek:

it won't be going on the viper--for now anyway. it'll be on the 18' hull it came on back when they were both new. the hull has potential, but it's super solid (so probably heavy). so we're not looking at an overpowered situation. if i get mid-60's i'll be happy. wife wanted a bowrider. i wouldn't get on board (pun intended), with some huge freeboard, I/O that you see all over the place on warm days.

https://lh5.googleusercontent.com/-j...0620-00079.jpg

-peter

OK, had to throw together an engine for my track car and have a baby and now I'm getting ready to send this 2.0L 150 fishmotor off to the machine shop. I've built a bunch of car engines but never an outboard.

What do I use for an engine stand? I have a bunch of car engine stands but the merc factory manual has some sort of stand that holds the crank and you build the engine around it. I don't have one of those. Do I need one? Or can I build this thing on a work bench? What do you guys do?

-peter

I use the old regular engine stand... not by the crank! Just set it up
to hold the block half (cylinders) Take your time and account for every
roller bearing! Good luck!

First of all make damn sure your machinist knows where to measure the piston for clearance and bore size.

thanks kings!

lynn, you said:

Quote:

---

First of all make damn sure your machinist knows where to measure the piston for clearance and bore size.

---

i will be using the marine-oriented machine shop mentioned earlier in this thread:

Quote:

---

Q & E machine in Anaheim. They do most types of outboard and watercraft stuff. My last three 2L's have come out perfect.

---

that's good enough for me. but now you are going to have me worrying anyway.

still lynn, i'm curious what if anything about fitting pistons to an outboard is hugely different from fitting them to a car engine? i'd imagine you make sure that after boring, the cylinder bore is round all the way down the depth of the stroke and not tapered, then inside mic it, then mic the piston across a couple of diameters and see if the clearance is right. is there something else? remember, the machine shop will be doing the mic'ing, but i'm still curious by your statement.

-peter

Eh, from past experience with a guy who argued with me on finish bore size even though I measured my slugs and told him exactly what I wanted, even so he measured at the ring lands and did what he wanted. Sounds like you are in good hands. 2 liter merc is a piece of cake.

ok so i bought a used powerhead off ebay so i can use it while i take my time on a good rebuild...

i'm also doing the water pump, because the reason the original melted a piston is some idiot ran it without water. sure enough the stock impeller is melted.

so i go and buy new parts for everything related to the water pump, and?

that blocky plastic base that you stack the pump assembly on top of... it was surprisingly cheap... only $28. but that's not the best of it. it actually came with the upper and lower seals already pressed in, gaskets, steel plate and o-ring. and even better still, that price $28 is basically what the two seals cost if you buy them separately. sweet.

sometimes you're the bug and sometimes you're the windshield.

-peter

James Perry on your machine work he loves the 2.0,2.4 motas and very reasonable :iagree:

if you gonna keep the cowl i got parts free for the shippin:eek:;)

why yes, i am going to keep the cowl. being brought up as an evinrude guy, this cowl is so incredibly funky, it's cool. so yes, i'm interested. pm me with what you've got. thanks. :)

an where is james perry? not in socal or nevada, i'm guessing? googling turns up nothing.

-peter

James is my machine shop man very good and in Dunlap Tn it would cost you 30.00 or so both ways shipping but you would save a lot more then that and IMHO better then who took over For Jim ruck oh so much better, i used some others also claiming greatness but it aint so, his sleeve work is unmatchable and so is his porting! he bores with torque plate and has ridged hone for great cross hatch honing:cheers: very nice work 423 304 0930

Quote:

---

Originally Posted by transomstand

Just wait till you step on the gas:eek:

---

lmao aint that the truth as far as the clam shell cowling I love them take it off and the whole powerhead is exposed easy to work on I wish I could fit one over a 260

Ok guys, a question... On this 1987, 2.0L 150hp, Do I keep that "idle stabilizer" module on the new (good used) powerhead or are they a trouble-prone headache that I'm better off without? My old old v4 crossflows have no such thing. But this is a newer and more complex thing, this motor is.

-Peter

i toss all boxs on every rebuild that i do" none"no idle stabilizer, no auto oiler, no detonation controller, no alarm's, only hot horn

thanks tex.

now another question about testing switch boxes:
this good used powerhead came with a couple of switch boxes. is there a way i can test these things before i slap them on the side of the powerhead? i have the factory service manual and it has you test resistance across some of the lugs to test the switch box. is it really that easy?

-peter

so the latest...

a couple of months ago, i bought a used 2.0L powerhead off ebay, swapped it over, and am slowly getting around putting it into use (i have other boats to use in the mean time). once done, i can take my time rebuilding the blown 2.0L powerhead that came free with a boat i bought, (a speedy, pad-vee hull bowrider).

before i test fire the new (used) powerhead, i've just been doing some basic checking: compression, spark on all cylinders, no fuel leaking when i pump up the bulb, enricher solenoid working, etc...

this being my first real merc, i just wanted to run the compression numbers on this '87 2.0L 150hp by y'all:

110/112
115/117
117/117

the top two are lower than the rest, which i am not losing sleep over, but are these numbers about right for the pump gas, fish/recreation motor that this will be used as?

-peter

Let her rip 89 octain will be fine with those numbers 145 -150 is max with 93 octain