Engine Mount Heat Protection Jacket

[Redd]

The E9x M3 engine mounts are perilously close to the exhaust headers and the radiant heat from the exhaust can cause damage to the rubber mounts over time. Even aftermarket mounts like Vibra-Technics are not immune to this heat damage, my VT mounts died after only 6k miles.

So I decided to see if I could build a cheap heat protection jacket for the new mounts I was going to install. It may or not may not help in the long run, but at less than $10 bucks and 15 minutes, I figure it can't hurt. Here's a quick summary of how to build these heat protection jackets.

1. You need some heat insulation material. I used this cheap wire/hose heat sleeve from AliExpress because it had the basic shape I wanted and was cheap, but you can pretty much use anything similar. You just need it to be reflective, heat resistant and flexible so that it can move with the subframe.
https://a.aliexpress.com/_mrhNxvN


2. Cut it into two pieces measuring 15 inches x 3 inches. I removed the top velcro strip but left the bottom one to give the base a bit more stiffness.


3. Wrap it round the diameter of the engine mount and staple it in place. I used my new Powerflex engine mounts for this but most mounts should be similar. The heat jacket should be about 4 inches diameter.



4. Punch 4 holes and cable tie (edit: steel cable ties work best) the heat jacket as below. After this you can remove the staples.



5. Slip the heat jacket over the engine mount. Add on an E46 engine mount heat shield (p/n 22111094624, $13 each) if you want.



6. During install, make sure to align the heat shield towards the exhaust headers and the cable ties away from the exhaust (in case they melt).


Enjoy! Downside is that it's impossible to eyeball the condition of the mounts now.

[SAMM3Y]

Cool. You could get stainless cable ties like what's used for header wrap or safety wire if you're concerned about the plastic melting/getting brittle and cracking.

[Redd]

Originally Posted by SAMM3Y

Cool. You could get stainless cable ties like what's used for header wrap or safety wire if you're concerned about the plastic melting/getting brittle and cracking.

You're right. But I couldn't find steel cable ties in time so just decided to risk it with plastic zip ties.

[Redd]

Long term review - 3 years and 22k kms later these heat jackets are still going strong. No issues so far.