New engine mounts don't fit - warped chassis?

[benymazz]

All,

I have a collapsed engine mount on the intake side (Weber head, original Lotus chassis). The failsafe part of the mount isn't banging on the chassis yet but it's pretty close (as is the airbox to hitting the footwell) and the mount is stretched and very, very flexible. When I reinstalled the engine a few weeks ago I intended to change it but found that I could under no circumstances make the new mount fit, so I decided to use the old one temporarily.

My theory for what has happened is that at some point in the past, I do not know how, the chassis became bent/warped/distorted such that the distance between mounting holes for the engine mounts is smaller than it should be, and my current mount has just been stretched out over time. I know for a fact the current mount is stretched in this dimension (I compared side by side to a new one I purchased), but I do not know for a fact that the distance between mount holes on the chassis is too small and cannot measure that now since the engine is in.

And before someone asks, I believe I have the right spacers for the exhaust mount. 1.125" length with a 120E-6015 block.

I'm planning on trying to fix this situation by using a combination of a short hydraulic body ram to "spread" the chassis a little bit and slotting the holes in the new engine mount. Without any spreading or slotting, with a new mount I'm currently off by a significant amount - I'd estimate at least 3/8" and probably more like 1/2" - so much that I can't even get the new mount "into position"; the rubber or side of the mount hits the chassis so I can't even get any bolt holes to line up, on the engine or on the chassis.

If anyone has encountered a similar situation before... please advise.

Thanks,
Ben

[oldelanman]

Have a look here ....

viewtopic.php?f=36&t=28670&hilit=+Engine+mounts

It seems some replacement engine mounts may be wider than the originals which might be contributing to your problem. There are dimensions in the above thread which may also help you determine if your chassis is distorted.
Also check that the mount brackets on the chassis aren't cracked.

[StressCraxx]

The new motor mounts I purchased about 5 years ago had the same issue. I contacted my supplier. He advised to slot the mount holes with a grinding burr or round file. I slotted holes on both mounts. The mounts installed without issue and worked great.

Regards,
Dan

[Elan45]

Ben,

Bring your mounts over and we'll compare to my new ones that are probably 10 to 15 years old. Monday PM is good and we'll fire up the green car.

Roger