Which motor mount?

ryan j · 10-29-2004, 06:33 PM

I've got a 3.2L in a '73 shell, and the rear motor mount broke over the weekend. The mount that broke is the kind with the threads inside the mount and no nuts at the bottom.

Do I have to use this same style, or does it not matter?

Which style is stronger?

Thanks
Ryan

Randy Webb · 10-29-2004, 07:22 PM

You mean the engine support crossbar?? The motor mounts are oblong and have rubber in the middle -- ?

If the former, the ones with threads are easier to use.

BTW, where did it break and can you post a pic?

ryan j · 10-29-2004, 09:36 PM

Yes, it would be the engine support crossbar then. Sorry, my first Porsche and I'm not sure of what the technical terms are for some parts.

This is on my rally car, and I had to run another 30 miles with a ratchet strap holding up the engine before I could get to service.
My service guys welded some plate over it so I could finish, so a picture of it now would show a rusty piece of metal welded over it.

The crossbar broke in a relatively clean vertical line about two inches from the driver's side mounting point.

poorsha · 10-29-2004, 11:16 PM

"Which style is stronger?"

"the ones with threads are easier to use"

They may be easier to use but I don't think they are as strong as the earlier ones.
It seems to me that when you have a bolt running thru the and a nut/washer on the bottom would provide a stronger fit (just my 2 cents).

Randy Webb · 10-30-2004, 08:05 PM

No problem re not knowing the terms. But it confuses everybody and you may get the wrong advice.... So, if not sure what it is called, just add a short description -- here, it was the bit about the threads that tipped me off.

re Poorsha's comment -- I think there is a thread on that very issue. As I recall we (being the geniuses that we all are) decide that one could just put a nut on the bottom of the threads if they ever do strip out. Someoone also did a stress analysis of these bars concerning the weakness induced by drilling holes in them. I take it that yours broke right at the vertical tube?

Anyway - use the gray Search bar in the blue header on the page -- type in engine support bar and you will find a lot of information. these items can be bought used - then powdercoated to look nice. If you have a lot of money to spend, you can buy stainless ones from soembody -- Renlline I think. Or you can just send the money to me for my light weight car project. Even if my car doesn't get lighter, your wallet will....