Motor mount thickness

[grdprx]

How thick should the motor mount be?  I replaced mine over the winter, one of a few projects I worked on.  Got everything back together, and now my exhaust pipes are up against the transmission cross member!      

Is it possible the brackets are on the wrong side or did I get some crap mounts?  I got them from Napa. 


The other winter projects were replacing the oil pan gasket, and a new torque converter which involved swapping the input shaft on my tranny.  So, nothing that would have changed the dimensions besides the new mounts.

Frustrating as heck.  The mounts I'd replaced were Old.  I suspeceted that maybe there was some seperation, wasn't the case, but they were worn.  The exhaust was bent and installed a year or so ago, so maybe the mounts were just compressed and now I'm screwed?

[ws23rt]

If the only change you made was replacing the motor mounts than the exhaust must have been close to the cross member before.
Not sure what you mean about brackets being on the wrong side? If you replaced part for part and they bolted up it should be good.
What I would try next is to  loosen the exhaust to manifold connections on both sides. (If you have an x or H pipe). Also loosen the motor mount bolts.
Try to shift the engine a bit in the mounts as the bolts will allow and pry and block the exhaust away from the cross member the best you can.
tighten all the bolts and see what you get.
If you can get at least 1/4" clear on the cross member It should be good. More is better.

[grdprx]

Thanks for the suggestion. I gained maybe an 1/8 inch or so, and now it rattles/bangs against the crossmember. I was referring to the engine motor mount brackets. Do they only fit on on side?
I think I'll have to compare mounts. The pair i got were thicker than I had and also had a thick metal backing. I had thought I got lucky, not getting a low quality Chinese piece...

[ws23rt]

Thanks for the suggestion. I gained maybe an 1/8 inch or so, and now it rattles/bangs against the crossmember. I was referring to the engine motor mount brackets. Do they only fit on on side?
I think I'll have to compare mounts. The pair i got were thicker than I had and also had a thick metal backing. I had thought I got lucky, not getting a low quality Chinese piece...

I don't know what the motor mount thickness should be. A replacement should be close to stock and firmer.
What is the difference between the two?
Your fix at any rate is to move your exhaust away from the cross member. It may be as easy as moving the pipes in their hangers. If not your eyes can tell where things need to move.
If old and new motor mounts are near the same than the fix for your problem is in the exhaust pipes.  (think easy fix--it works best)

[green69rt]

I don't know if this will help but here are pics of the motor mounts off of my car (383).

[grdprx]

Thank you for the picture!  

Mine are also 1 3/4 inch, although they are installed and thus compressed. I would imagine that's correct though. I haven't got a clue what my problem is. My exhaust was installed a few years ago, I didn't notice a problem before, but I wasn't looking. I do recall being able to move the crossmember after unbolting it from the trans, while the exhaust was still attached... My old mounts are gone unfortunately, so I can't compare the old ones.

[firefighter3931]

It's a simple fix : Pull the mount off the car and trim the rubber down to lower the engine. Problem solved 


Ron

[green69rt]

Thank you for the picture!  

Mine are also 1 3/4 inch, although they are installed and thus compressed. I would imagine that's correct though. I haven't got a clue what my problem is. My exhaust was installed a few years ago, I didn't notice a problem before, but I wasn't looking. I do recall being able to move the crossmember after unbolting it from the trans, while the exhaust was still attached... My old mounts are gone unfortunately, so I can't compare the old ones.

I checked mine again cause the picture didn't show the thickness very well.  The actual rubber is 1 1/4" thick as they set outside the car.  If you need any more measurements just let me know.

Mitch

[grdprx]

Thank you for the picture!  

Mine are also 1 3/4 inch, although they are installed and thus compressed. I would imagine that's correct though. I haven't got a clue what my problem is. My exhaust was installed a few years ago, I didn't notice a problem before, but I wasn't looking. I do recall being able to move the crossmember after unbolting it from the trans, while the exhaust was still attached... My old mounts are gone unfortunately, so I can't compare the old ones.

I checked mine again cause the picture didn't show the thickness very well.  The actual rubber is 1 1/4" thick as they set outside the car.  If you need any more measurements just let me know.

Mitch

Thanks Mitch.  Was finally able to get mine out of the car.  Been busy with summer activities.  My rubber is also 1 1/4".  If I recall correctly, the mounts I replaced were noticeably thinner.  Looks like my custom exhaust was installed pretty tight.

It's a simple fix : Pull the mount off the car and trim the rubber down to lower the engine. Problem solved 


Ron

Ron, got any suggestions on the easiest way to trim the rubber?  I think the easiest would be on a band saw, but that's on my Christmas wish list; and I'd hate to rubber up someone else's.

[firefighter3931]

Ron, got any suggestions on the easiest way to trim the rubber?  I think the easiest would be on a band saw, but that's on my Christmas wish list; and I'd hate to rubber up someone else's.

I'd just get the mount in a vice and use a hack saw.....should only take a few minutes to saw through the rubber. 


Ron

[69rtse4spd]

If you know anyone with a disk sander, that will work to.

[John_Kunkel]

Both sides of the rubber insulator are bonded to a steel plate....no exposed rubber to trim.

[grdprx]

This is one time that cheap foreign made parts worked!  I got some mounts from napa, that I had previously rejected, that were made in India and Korea.  My issue seems to be solved, I test drove it today.  The Indian one was the thinnest, the Korean was an eighth or so thicker; but they seem to clear the exhaust from the crossmember so far.  I didn't get to put too many miles on it tonight, but so far, so good.

[green69rt]

That's a big difference!!!  Did they give you the right mount the first time??

[grdprx]

These are the same part #, different vendors. The big one is the same measurement as yours. Thanks again for your help, by the way.
I had old mounts on the car when the exhaust was installed, they did it high and tight. Not necessarily wrong, but I'm not going into my thoughts on that install job...

I'm back on the road!