I have a set of prothane poly motor mounts on my ls2 in my trans am. The car has run for a total of 1 hour 45 minutes over 3 days. When I went under the car today, I saw some melted black rubber. Upon further inspection I realized the driver side motor mount is melting inside the clamshell!

What can I do about this? Has anyone else had this problem? Why is it happening?

 

header primary too close to the motor mount? motor Overheating? Kids with lighters?

 

You need to install heat shields like this; buy or make them.
http://www.ls1gto.com/forums/showthread.php?t=283706

 

no something sounds wrong... i have a ls3 with the same motor mounts (i guess, like the high energy brand or similar style?) been running strong and no melting.. no heat shields either...

 

Thanks guys.

The header primary is not that close and the motor hasn't overheated. I have a plastic zip tie closer to the header primary than the motor mount and its not melting. And those pesky kids with lighters haven't been around here in a while.

I should have specified. They are LS1 style motor mounts on an LS2 since it is in a Trans Am.

Could this one particular motor mount just be a bad part? The other one which is closer to the header primary is still in excellent condition.

 

I have prothane poly mounts in my T/A with a L92/LS3 block, and haven't had any problems. My Kooks headers are ceramic coated though, and I'm pretty sure the driver's side mount has the stock heatshield over it. Is your heatshield not there anymore?

 

I had poly mounts on my car for a year before I swapped to a motor plate with the big motor... and had no issues. I think you got a defective set or something.

 

That's what i thought too JL. I am not looking forward to having to fix this problem.

 

Did the car have heat sheilds on the stock mounts, and did you resuse them? Possibly just a bad mount...

 

I did reuse the heat shields.

 

i would put the stockers back in. imagine being on a trip 100* out and that **** pops on you. eff that noise.

 

It has been replaced. Thanks everyone.

 

i just checked mine yesterday.........all good