260 Mercruiser - Rear Engine Mounts

[1981century]

Okay, I finally had some time over the holiday weekend to put my bell housing on with the new rear motor mounts pressed in. I am working on the 1981 Mercruiser 260 that I have posted about in the past. I couldn't get aligment and found out the rear motor mount had failed in the rubber portion of it. Luckily, no coupling, or splined shaft damage. So I get the bell housing back from the Marina and they glued the fiber washers from the kit to the top of the mount. That has to be wrong, so I managed to remove them in one piece with a razor blade. The guy at the marina must have had a brain fart or something. Anyway, they pressed the mounts in, (hopefully correctly) although after having to remove the fiber washers, I have my doubts. The guy gave me the old motor mounts back in a plastic back and also gave me two new washers that came with the new motor mount kit. He said you would need to use these washers along with the fiber washers. So I got the motor dropped back in the hole using the fiber washers and the stainless steel washers that came with the new kit. (I chunked the spring washer and fiber washer that went with the old mounts.) A quick check of the alignment suggest I'm way off. Surprise surprise. Do I simply need to remove the stainless steel washers, and only use the fiber washers? It looks like the stainless washers are holding the motor too high. Shouldn't the fiber washers have a little pressure on them when everything is bolted down. Witht the stainless steel washer, there appears to be too much room between the bell housing and the gimbal housing mounts? Has anyone out there dealt with the new replacement mounts and know what to do?

 

[NHGuy]

Re: 260 Mercruiser - Rear Engine Mounts

deleted. Pete

 

[Bt Doctur]

Re: 260 Mercruiser - Rear Engine Mounts

It is acceptable to glue the fibre washers in place.You need to try adjusting the alignment
first using the front mounts.IF you cannot obtain alignment then:
the ss washers can be removed and attempt alignment
the new mounts are not fully pressed in place

 

[1981century]

Re: 260 Mercruiser - Rear Engine Mounts

What do you mean the new mounts are not fully pressed in place? Are you saying I need to pull the flywheel cover back off and make sure they are fully pressed in place? The marina did this, but since they glued the fiber washers on the top of the flywheel housing, then I don't know that I trust them to have done everything right. It appeared that the mounts were pressed in properly, but it was hard to tell if they put the little beveled washers in right or not. Shouldn't the fiber washers be tight between the mounts? I undertand that the adjustments are made with the front mounts, but what doesn't make sense to me, is that the rear mounts are pretty much right in line with the splined coupling so it would seem that there would only be one position that would be right. Does the gimbal bearing float in its mount somehow, then the u-joints align the rest? It would seem that there would only be one way for this rear mount to be set in order to align with the gimbal bearing. Thanks for the posts.

 

[Don S]

Re: 260 Mercruiser - Rear Engine Mounts

It sounds like the shop installed new OEM mounts, which means you will not be using the double wound lock washer. This service bulletin shows the new mounts and how the hardware fits together.

The mount going into the flywheel cover goes in spacer first to the stop, then the mount up against the spacer.

.

 

[Speakrdude]

Re: 260 Mercruiser - Rear Engine Mounts

If the rear of the engine is too low and you cannot lowerr the front of the engine enough, you need to re-install the old double-wound spring washers, in addition to the shims with the new mounts. I spent about 4 or 5 hours trying to figure this one out. Finally called Mercruiser customer service and they confirmed, that using the new mounts with and old engine 95 and earlier, you MUST re-use your old spring washers. Did that, worked great! I almost cutdown my motor mounts trying to fix! Was at my wits end.

 

[1981century]

Re: 260 Mercruiser - Rear Engine Mounts

Okay I will post my results for others to benefit from as soon as I get it right. Thanks everyone for your input.