Is this engine mount correct? Have pic.

[90stingray]

I bought this boat about 3 years ago... had everything check out when i bought it. Its always seemed like the engine vibrates the boat when running, more than i thought it should. Passed it off as a 20 year old boat. This spring I have checked bellows, changed gimbal bearing, etc. I checked alignment and all is good. I am wondering if these engine mounts are the culpruit to my excessive vibration feelings. It seems like the plate is hitting hard on the rear of the mount. These are the "fluid mounts." What do you guys think? How could i fix it, if its bad?

 

[Pete104]

Re: Is this engine mount correct? Have pic.

It don't look very comfy! How 'bout removing the lag screws? Lifting the front of the your motor (just slightly) & see if they come back to square & true. Problem's are; #1 why is it there now? #2 Now you have holes to fill in the engine bed, which may or may be rotten wood. Not good news but very possible!

 

[90stingray]

Re: Is this engine mount correct? Have pic.

Thought about trying to mess with the mounts but the alignment is all good and don't really want to pull the drive again. I will if I have to. What is that plates purpose? Other than holding my engine in alignment How would I go about getting away from the metal to metal contact other than unlagging mounts? Let me know what you all think.

 

[zbnutcase]

Re: Is this engine mount correct? Have pic.

Those are the old fluid filled mounts they used on pre balance shaft 4.3's, and yes they certainly could have issues. Or engine could have issues...has a compression test been done lately?

 

[90stingray]

Re: Is this engine mount correct? Have pic.

Compression test 165-175 across all cylinders. You think the mounts could be bad? Why are they called fluid mounts? Is there fluid inside? Could they dry out? If I need to change them... would or could I go with an older or newer style mount?

 

[Don S]

Re: Is this engine mount correct? Have pic.

The reason for the fluid mounts was to smooth out the vibration at idle. They were on the V6 engines before the balance shaft. Your mount is flat. and that top plate should be up around the round balls on the cable.
They are still available, but expensive. 18098A3 is the part number.
The mount should have been on a wedge to keep it perpendicular to the mount stud.

 

[90stingray]

Re: Is this engine mount correct? Have pic.

Can i just make a wedge? Would one come with a new mount? I looked that p/n up and it's obsolete. Is there a newer p/n? Don... If it were you, what would you do?

I just took her out for a test run since i changed gimbal bearing, etc. I should have changed u joints... they make noise at idle, at full steer L or R:facepalm: Guess i could never hear them with the old gimbal bearing. Have other issues too but that's another thread.

So, anyways i will be pulling the drive again and i want to do the engine mounts and make 'em better.

 

[Don S]

Re: Is this engine mount correct? Have pic.

http://www.marinepartsexpress.com:8080/mpeCart/details.faces?productId=18098A3&Go.x=20&Go.y=17&Go=Go

I just took her out for a test run since i changed gimbal bearing, etc. I should have changed u joints... they make noise at idle, at full steer L or R Guess i could never hear them with the old gimbal bearing. Have other issues too but that's another thread.

If you had water in there, and the gimbal bearing went bad, the ujoints should have been replaced at the same time. The other thing is the input shaft seal in the drive and possibly the yoke. If the yoke was rusty, that cuts the seal and there goes your gear lube. Now you're running the upper with no gear lube .........

See where this is going ??????

 

[90stingray]

Re: Is this engine mount correct? Have pic.

A little off subject but i will explain my situation...

I bought the boat 3 years ago... and right away had someone change shift cable, bellows, inspect everything, etc. Since i bought it i always thought it was noisy and rough back there. This spring i talked myself into pulling the drive (a first for me) and do my own work. I have never messed with a sterndrive before... but feel more confident now that i have seen what is going on inside. I made a drive stand, bearing puller, bought all the alignment tool, bearing driver tool, changed gimbal bearing and seal, checked alignment and reinstalled drive. The bearing was not rusty... just rough. U joints felt good but apparently are not. So i will change them but the rest of the sterndrive looks good.

Back to the mounts... mine are flat and bad? Can i go with the older style p/n 814263a1? or 66284a2? They are like $30 each. If so, would i have to shim them with a wedge or some sort?

 

[Don S]

Re: Is this engine mount correct? Have pic.

They can't be any worse that your dead fluid mounts.
What you need to do is keep them as square as possible to the engine mount, and when aligned, have the engine mount about midway on the mount stud. Shims are often used. I have used aluminum, and poly (Not brittle plastic) for engine mounts.
The stringers aren't usually that far off and needing a wedge.
Get the alignment about right, then drill and mount your new mounts solid and do the final alignment.