Wednesday, September 23, 2009

Replacing engine mounts

For some time now I have recognized that it was time for me to replace my engine mounts. They are orginal to the motor installation in 1988 and by any criteria it is high time to replace them. In addition, I have known I have an oil leak somewhere, and it was either my rear main oil seal or something related to the oil pan, neither of which can be accessed without raising the diesel off its mounts.

Once we had returned from our amazing August trips into British Columbia, I figured it was a good time to launch into this major project because I had satisfied my need for sailing time and wouldn't need to be out on the water for a few weeks.




When I had the new prop shaft and dripless shaft seal installed in Portland in 2006 they did a cursory engine alignment and thought it was pretty close. I was always able to spin the shaft freely by hand and so knew the alignment was pretty close, but at my last haulout was a bit concerned I was developing some signficant free play between the shaft and the cutless bearing which could indicate an out of alignment engine.

That's the back story.

To lift the engine the Gulf 32 is pretty ideally arranged. I was able to lay two 2X4's across the pilothouse top and the alignment between there and the lifting eyes on the motor is perfect. With a come along I was able to lift the motor straight up a few feet, giving me plenty of access to everything. The hardest part is removing everything from the motor that would be torn off if you left it in place. I donated yet another large amount of skin to the boat while doing this. All the electrical wires and various plumbing hoses have to be removed. Before doing this you have to remove all the coolant.


Anyway, once the motor was raised, I had no trouble removing the old mounts. They looked corroded and worn, but the rubber didn't look too bad. Only one of them had significant compression of the rubber, and that one is shown here.

I got the new mounts in place and adjusted their bottom nuts to be about where the old nuts had been. Lowering the engine back down was easy too. The mounts I used were: BUSHINGS INC, part number : DF-2207-2, description : Dual Flex Engine Mounts, 4" bolt centers, 5/8" stud, for engines 450-750#'s from Torreson Marine. 


I have mated the prop shaft with the transmission flange but haven't taken the feeler gauge to the alignment yet. That is well known to be the tricky part. I'm allowed .003 of an inch maximum discrepancy, and that's not much.


I don't know if I'll be lucky or not, but I'm signed up for a few weeks worth of trouble.

3 comments:

Unknown said...

Thanks Brian, I looking at replacing my Yanmar 2GM mounts this year and appreciated your post.

Arya said...

Love your blog, Very helpful.
The engine mounts on our Gulf 32 are worn out and I am having trouble finding the right replacement. Where did you get yours? And can you provide a part number?

Brian W. said...

Hello Arya,
I should have posted that in this old blog post and now it's been a while so I don't recall off the top of my head. But next time I go to the boat I will look it up in my maintenance log where I probably recorded that information. Check back and I'll update the post. Glad you find this stuff helpful.