Replacing Mounts w/o Pulling Engine

[AaronJ]

My mechanic told me he can replace the Yanmar 2GM20F motor mounts without pulling the engine out. He suggested supporting the engine under the oil pan with a jack and replacing the mounts one by one. Does anyone have experience with this? It doesn't sound like rocket science, so I'd like to do it myself...including shaft alignment afterward.

[James S]

I would not support the engine under the oil pan unless it is designed to hold that kind of weight and I have no reason to believe they are.
But you can certainly change the mounts as he said but support under more substantial areas.
You may also be able to hang/support from the top.

[imagine2frolic]

What about using the boom for a support to lift the engine? This is how I removed my motor. Tied the halyard over where the lifting point was to be. Wrapped a strap around the boom with block, and lifted.......i2f

[Tellie]

One way, there are a couple of unused threaded holes on the side towards the back of the 2GM20F. I made a small 90 degree bracket that could be bolted to those and then used a jack to life one side at a time to replace the mounts. This job certainly can be done without removing the engine. I would frown upon jacking any engine by it's oil pan.

[limmer]

Totally can be done I just finished this job myself and had the same conversation with my local mechanic. I rented a jacking kit which came with a scissor type jack or spreader type this worked great for the tight areas. I disconnected the shat from the tranny and replaced one mount at a time alot easeir than I thought it was going to be.

[donradcliffe]

The oil pan may be strong enough, but if you support the engine on it the pan gasket will start leaking oil, especially from British engines which still use cork gaskets...the voice of experience.

[r.furborough]

The oil pans on Yanmars are generally cast aluminum and can take the weight of the engine. When lifting the engine some have tried using a deflated basket ball and then inflating it to lift the engine with success.

[MidLandOne]

I am not too familiar with the particular engine but as far as I know (I may be wrong) the feet on the engine that the mount stud goes through are removable. If so can you not just remove them one at a time - foot and mount all in one piece - attach the new mount to the foot and bolt back onto the engine?

The engine will sag a little in the corner the current mount and foot is off as the diagonally opposite mount goes into tension to support the engine but the adjustment in the new mount can be used to jack it back up again.

[senormechanico]

I2F described exactly what I did to fix a leaking oil pan, but instead of just a loop around the boom, I also added a line as an outhaul.
Between the halyard (vertical lift) the outhaul (fore and aft control) and the traveler, I had 3D control of the engine. I just hung it to remove the pan from the comfort of my cockpit.

Of course, you only need to lift it a few inches,, but the same theory might apply to your situation.

Steve B.

[Maddog]

My mechanic did it with a hydlaulic press, lifting each foot one at a time. Very simple.

[Pblais]

My mechanic did it with a hydlaulic press, lifting each foot one at a time. Very simple.

That really is the easy part. Doing the shaft alignment is the part that is not so simple. The good news is you don't do that untill you replace the mounts. All of them is just the only way to go.