Logo

1991 omc 3.0

crank shaft pulley is spinning. I cant find one bit of info or part #'s for replacement.

Looks like the pulley itself has broke lose of the crankshaft hub. Sound right or have you seen or heard of this?

Its like the pulley is just dancing on top of the crankshaft hub.

I dont even know if I have a ford or chevy 3.0 block. cant find data tag that is said to be on the valve cover. Is there a chance I can replace pulley or whatever this assembly is with car version? I dont see a balancer just looks like a pulley on crankshaft. Not sure and have no clue.

Anyone have any insight?
 
I lifted engine up and removed the damper. It's shot. The pulley was just sitting on damper. You can see the elastic laying on floor. I can't find a damper. Anyone have any Idea's.
 
Thanks guys. I did a pile of searching yesterday and I found it at two places but lord that's a pile of cash for a damper. Man oh man. And I really dont know if it will run. Also found out starter caseing is busted.Damn the luck.

Still worked on it. Got it to turn over with starter as is so i know its not froze up. Turned slow thanks to weak starter. I put what was left of blancer back on just so I can fire it up to see if it will run before investing in a new damper for no reason. Think you guys would agree. So today I hope to get it to fire. Got some starter wireing issue. Cant seem to locate the S wire for starter. I will get it figured out. I will post update. Thanks for the help guys.
 
Holy crap. Is that the right one? he says came off MC which is not the OMC that I have. Are they same? Sure looks right. Good price and I need to jump on that as soon as I here you guys say its the right one.
 
it's all the same block a 3.0 omc and the merc one.

I have right now in my boat a merc motor 3.0 / 140 hp after i yanked out a 2.5 omc .

The mani fit but back to your question it's the same. Call the guy or send a email and ask him how many dollars he wants.

Say you don't get that one you now know where to look.

And your welcome.
 
I hit him up this morning and he did reply that I would have to wait out the auction. I do need it cause I just got engine running and seems to run fantastic. Fired right up. Now I just need this so I can put belt on and pump water.
 
And I really dont know if it will run.

sounds like a project scow.
might want to pressure test the cooling system before spending a penny on it. At least remove the adapter on the bottom of the oil pan and see what flows out first, water or oil....
 
I checked oil and it looks awesome. I have no idea what adapter your reffering to. Would that be the tube that comes up side of block with what looks like a water hose end on it?
 
I checked oil and it looks awesome. I have no idea what adapter your reffering to. Would that be the tube that comes up side of block with what looks like a water hose end on it?
yep, if you mean you simply pulled the dipstick.... keep going... hang upside down in the bilge and take that line off the pan - hopefully it was winterized- you'll be the first to know if it wasn't

undoing that fitting is the first task in the inspection of any project boat or parts boat
 
Last edited:
anyone happen to know where to get specs? not much to be found. Wondering things like how big is fuel tank and etc. Fuel gauge dont work. Would be nice to atleast know how much fuel it holds.
 
What make of boat ? they have the specs.

But is you tell us maybe we know.

That hose attachs to the drain of the pan. You pull it out of the drain hole in the bilge to a bucket outsdide the boat to drain the oil pan.

Understand grasshopper ?
 
no you just inscrew the plug in the end of the hose.

That hose it's connected to the drain on the pan ??

your pulling my leg right?
 
Not sure. Let me explain what I know. On the side where the dip stick is there is a tube with a cap on it. The cap has a little chain on it. The tube is metal. Its not a hose. I followed it and it goes to the back of the pan at the bottom. The top where the cap is looks like the end of a water hose.

But now that you say something about a hose I did find something weird yesterday. I found a hose that seemed to go to nothing just laying there. I followed it and it also seemed to go to the rear of the pan but not 100% cause I did not spend much time with it. But the metal tube 100% sure goes into back of pan.
 
Ok Balancer is on. Engine fired right up. I got to test with water hose and muffs. All is well. Then after about an hour of running I see there is alot of water building up. I check things out and though its really hard to see back behind the engine I can see water streaming while engine is running. Then with my hand I can feel it is coming through a hole? Is this normal? Its a hole in the very back.
 
You mean a casting plug sometimes called a freeze plug, A problem you say you don't have cause it never freezes in FL

Look in the bilge see a round metal piece that has a raised edge.

Not for nothing HY knows his chit.

Understand grasshopper ?

Now i don't think you can get to that plug without pulling the motor.

Want to know how to do that cause if you got a casting plug out you may have cracks in the block also ?
 
Sorry I should have been more clear. I was quite tired last night. The its not a freeze plug because the water is not coming from the engine. This a hole about the size of my pinky finger directly above the rear drain plug. I would say its about 2 inches above the drain plug. Not coming from the engine.

While its running the water leaking is cold as if its fresh incoming water.
 
You have a manifold drain plug and a block drain plug. What year omc is this?

Got a pic ?

You got to help us a little to help you.
 
Well its been a few days and few things have happened. I took boat to the lake Friday afternoon and rode around testing things out for a few hours. Went very well. I got a top speed of 36mph with just me in the boat. That was good. Motor ran strong and frankly was very pleased. I did notice after getting boat in the water and coming back from parking that the well had pretty much filled with water. I turned on bige pump and it cleared it out. While cruising no water comes in over course. The temp gauge was reading a high temp at WOT and the ignition switch was giving me hell. So anyways I brought it home. Went down Sat Morning and picked up new ignition switch and an impeller. Replaced both. Did some more feeling around with regards to the water leaking in. (Is it the gibson?) there is what seems to be a bracket that goes around the back of the boat (inside) for holding perhaps the stern drive to the boat. Anyways what I found was that if i put my hand up a bit further I feel the void where I guess the the exhaust goes out. You can put your hand right under it. That is where the water is coming from. I could feel below and felt the wood which I assume is between an inside and outside layer of fiberglass. It was all wet. the wood is worn enough away the water coming in just comes out of the hole in the bracket I pointed out before. So what I have is the water is coming in while sitting in the water via the exhaust or somewhere around it from outside of boat. Have no idea how to fix or where to start.

I took wife and little one out yesterday after fixing what I wanted to. Wife really wanted to get a feel for it. She is looking forward to taking the kids tubing. Lake is right down the street. Anyway it was flawless. Motor ran awesome. Not one hick-up and was amazing. Motor runs strong and cool. Oil pressure stays around 50psi WOT and 20 at idle.
 
I'll send a picture of anything but can't send a picture of what i can't see. I can only feel with my hand. One min and I will post pictures of boat
 
IMAG1317.jpg

IMAG1318-1.jpg


 
Back
Top