burnt engine rubber mounts

While the rubber mount biscuits will wear out in time, I've never heard of one burning out. There have been some mis-guided souls that came up with poly motor mounts, thinking if poly suspension bushings were good, then why not for motor mounts, too? Well, because they melt and burn being that close to the headers, that's why. Could you have such a problem? Whatever, get stock rubber and I hope that cures your problems.

Larry

Typically, their life is much longer, but catayltic-equipped GT5-S cars may put more heat than normal into the area around the aluminum engine mounts. The rubber spacers tend to squeeze wedge-shaped after decades of use on pre-L and L cars, which then forces the motor mount-to-block bolts to bend & break. So on those cars, every decade or so its advisable to unloosen things and rotate the rubber 180 degrees to distribute the load. One thing we know DOESN'T work though is polyurethane replacements for stock rubber. Even in a pre-L or L car, the urethane will liquify from header heat, causing much trouble even getting the motor mounts out of the area, to be chiseled apart! On your car, I'd check the bolts holding the upper mounts to the block, as it sounds like the engine is pretty unsupported now. There's also a long bolt holding the two halves of each motormount together; its often put in with the nut upward, which is not correct. There's a drilling in the end of the bolts for a cotter pin, so if things loosen up, the nut won't unscrew & let the bolt drop onthe road. Many Panteras have the bolts in backward.

Stephen,

this topic came up in the tech-session
at last years Vegas Rally. I seem to recall
that Kirk Evans reccomended installing
heat shields to protect the motor mounts.

You might want to contact him for
clarification. Does anyone else remember
the discussion from last year?

John

I had the same problem with my left engine mount rubber.
After installation of a home made aluminium heat shield, the problem was solved.

PS: Why cant we post any pictures here?
I could make a photograph of it, and it would be a benifit for everyone

Paul.

thanks guys for your advice, I replaced the engine mount bushings with factory items last week with the help of a local garage at his premises, appears the ones in the car were polybushes, as they had hardened and broke apart almost like glass!! the centre had also become oval allowing the motor to move forward, unfortunately the aircon pump was damaged through rubbing against the firewall. the motor has been fitted with the Hall Pantera tooth drivebelt system which appears to lessen clearance between the motor and the firewall. only very slight occasional rubbing of the aircon pump pulley against the back panel now when braking hard, but the motor is well clear of the bodywork with the new bushings, also made a heat shield from aluminium bent at a right angle over the mount assembly and bolted on.

I'm just now experiancing the same thing with my catalytic stricken GT5-S...The thing
just now grazing the bulk head part of the body work is the air pump.(makes a chalk and fingernail screeching sound...lol)Fortunately i'm pulling the engine so will remedy motor mounts and/or whatever else it might be.I like the idea of fabing some heat shields for mounts to..

Yep, making the heatshield is easy, I used aluminium, but into a cone shape with the narrower side to the top and drilled a hole through which the engine mount bolt goes, then bend it in a 90deg angle to cover the mount assembly, my car isnt cat equipped, but is mildly tuned pushing out about 430hp

For you wide-body guys with clearance issues between the air pump & firewall, you can gain a bit of clearance by loosening all the motormount bolts and removing any ZF mount shims in the rear of the mount, then prying the entire powertrain rearward the maximum amount. Or, by re-drilling the motormounts, even more clearance can be had. The simplest and best mod of course, is to discard the air pump, move the stock alternator up where the pump was, buy ane upholstered flat firewall cover from Pantera East, and not only will there be no more rubbing but the passenger seat will go back as far as the dtivers, for more legroom!