Squeeky noise from back of engine-->Coupler??

[Mike_Maranto]

Hi,
94 Mercruiser 5.0, alpha 1 gen 2, replaced bellows, replaced Y pipe, pulled engine, aligned engine before installing the drive. Gimbal bearing good no play and very smooth.(many thanks to people who helped me every step of the way towards successful repairs)

Second time pulled the drive (within a month) when exhaust bellow came off, the drive was in trailer position; replaced the bellow with sierra part, after launching the boat, squeek in idlle after 5 minutes, high rpm no squeek. The drive went in upon installtion like knife on butter
Every time I pulled the drive lubricated and greased the spines and bearing religiously, coupler only once.
Totally lost now what went wrong. I see some grease under the coupler also. There are few weeks of summer left and it seems I would never enjoy my boat worry free.

 

[Mike_Maranto]

Re: Squeeky noise from back of Engine

Re: Squeeky noise from back of Engine

Ok guys I think I got the problem nailed, the studs that hold the engine in the stingers are bit loose and I can't tight them enough and probably this threw the engine out of alignment a bit. I will post once I get a solution how to make those screws tight, either pour something in the holes or use thicker studs I don't know yet. If any one has any suggestions please post

 

[erikgreen]

Re: Squeeky noise from back of engine-->Coupler??

Edit: Just re-read your post, and I thought there's a slim chance the "studs" you're referring to are the height adjustments in the forward motor mounts themselves. If that's the case, then there's still a problem with your lower mounts, either they're the wrong height to begin with or they're rotting and sinking.

--
I'm going to give you a straight answer here which you probably won't like much.

The loose screws (lag bolts) in the stringer mean the stringer is probably rotten. This is very common in older boats, especially at that spot. Water leaks in around the bolts easily. There are plenty of boats with this problem in the restoration section of the board here.

To fix it, the right thing to do is replace at least the rotten section of the stringer. This means pulling the engine out, cutting the bad wood out, then glassing in new and re-installing and aligning the engine.

If you are going to do that, read up here on checking for rot elsewhere in the boat, and check before you start work. Lots of people find more rot as they look. Unfortunately, it's a can of worms.

As to a fix that fills the hole... probably not. If the problem is rot (most likely unless the boat has been in an accident) then the filling will wiggle just like the bolts. The only way to get it back in alignment with bad mounts is to shim it up into place... use an alignment bar from the rear to tell when it's good. The shims themselves are going to be sitting on rotten wood, so they may not last long, and the mounts will continue to subside, putting the engine out of alignment again. Fortunately the rear mounting bolts hold it in place port/starboard, so you only have to worry about vertical angle.

If you take the quick fix, make sure you check alignment with the alignment bar every trip or every other trip before you go out, and take oars or a spare motor (kicker) with you in case the coupler goes. Eventually the mounts will be gone and you won't have a choice except to replace them or junk the boat, though.

Good luck,
Erik

 

[wire2]

Re: Squeeky noise from back of engine-->Coupler??

Put a cat in there to catch the mouse?

 

[Mike_Maranto]

Re: Squeeky noise from back of engine-->Coupler??

Erik, thanks for the detalied reply, I agree on rotton stingers but this boat's stingers are in good shape, yes I redid the whole cabin that was rotten and it was like a can of worms, never the less I took the approach to do it right the first time.

My boat's deck is fiber glass and upon inspection under it the wood was dry as it can be and solid, I was not hoping this after I saw what was in cabin. I inspected the boat all the way back to stringers and transom

The studs I referred to are the studs that go in the stringer towards the back away from coupler, the stringers are in good shape, the only thing went wrong is that the marina guy who was helping me used the wooden shims to fit the studs, at that time I was away to get lunch: I should have asked not to touch anything, upon my return I aligned the engine and the drive went in without any problem.

Since yesterday I pulled my merc manual and reinstalled the studs (the manual talks about front bolts and the adjustment to them), I was able to tight one side really good, the other side only one stud is loose, as the guy informed me he used shims to snug studs in and he hammerd them in, he also used a thicker bolt that made the hole diameter bit bigger. You think one loose stud will make a difference, I was hoping to fill it with some putty.

My next step will be is to reinstall the front engine bolts with proper washers and with right torque but before I tight them up I will realign the engine. I will lubricate the alignment tools's front with alot of grease and upon pulling it out I will inspect where the greese has deep mark, this will give me an idea either to lift or drop the engine.

If I get even the slightest feeling that stringers are bad the engine is definately coming out and job will be done the right way.

Many Many THANKS for your great reply.

In any case I will NOT go with quick fix, I have read alot of posts on rotten stringers and transoms.I am type of guy who likes to do things right the first time as some one said we don't have enough time to do things right the first time but always have alot of time to do them over

 

[erikgreen]

Re: Squeeky noise from back of engine-->Coupler??

The studs I referred to are the studs that go in the stringer towards the back away from coupler, the stringers are in good shape, the only thing went wrong is that the marina guy who was helping me used the wooden shims to fit the studs, at that time I was away to get lunch: I should have asked not to touch anything, upon my return I aligned the engine and the drive went in without any problem.

Since yesterday I pulled my merc manual and reinstalled the studs (the manual talks about front bolts and the adjustment to them), I was able to tight one side really good, the other side only one stud is loose, as the guy informed me he used shims to snug studs in and he hammerd them in, he also used a thicker bolt that made the hole diameter bit bigger. You think one loose stud will make a difference, I was hoping to fill it with some putty.

I'm not sure what studs you're talking about here.

The way my motors are mounted is with a pair of "legs" on the forward part of the engine, which look like these:

The gray part in the pic screws down into the stringer or motor mount with two lag bolts, the black parts in the pic bolt to the engine, and the threaded part of the gray section provides vertical adjustment.

Do you have a different set-up in your boat?

Erik

 

[Mike_Maranto]

Re: Squeeky noise from back of engine-->Coupler??--Update

Re: Squeeky noise from back of engine-->Coupler??--Update

Erik the setup I have is same as in pic but the stringers mounts are bit heavy in looks. In my posts I think I was confused with front and rear mounts, the front ones are adjustable(the ones on stringers) and serve as pivot where as the back ones are fixed, any how UPDATE on the noise, the squeak was from loose transom bracket, I tight it up and the noise went away; I also checked the alignment with grease on the tool, the top part of tool has no grease where as bottom part had grease left when I pulled it out, also the tool went in with very little force not as many of treads mentioned two finger push rule. Let me know what you think? Should I drop the engine a bit from back?



Thanks for the image.