Hello, I just signed up today.
Can someone tell me what seam sealer is used under the floor pan, above the catalytic converter? My 2003 350z Touring, had a clogged converter. I removed the exhaust system cat back. The seam sealer above cats, turned brown, (was white), and some chunks fell out from the excessive heat. Before I install the Berks free flow cats and Invidia exhaust, I will scrape out all sealer that turned brown, and then put on new sealer.
Thanks

 

Dont know why you would go through all that trouble but you can get 3m seam sealer. I wouldn't imagine the exact same product Nissan used back in 03 on an industry level would be available in a consumer package.

 

Some chunks fell out. I searched for seam sealer online. But couldn't find one stating how high a temp it can take.

 

If it worries you I would just use high temp rtv silicone, it would serve the same purpose. Think they are good for 700 degrees or so.

 

I used 100% silicone from the home depot on my fenders once I rolled them to keep moisture and salt out. Its held up well.

 

Thanks dboyzalter, I'll probably try that.....

 

Yikes, are the CAT heat shields missing? I would definitely re-install some kind of heat shielding once you have things sealed back up. I know people have complained about vibration noise from the OEM heat shield there, but this can be easily mitigated.
-Icer

 

The Cat shields were on.
When I pulled in my driveway, white smoke was coming out from the left cat area, It smelled a little like electrical fire and the interior smelled like ammonia. I lifted the hood and the smoke was coming up from the back of the motor.(cat).
I used a HF laser thermometer. The front of the pipe on the left cat was 958*. The pipe at the rear of left cat was 500*. After about 20 minutes, I checked the carpet under the 2 floorrmats the previous owner had on the drivers side only. The temp of the carpet was 186*F.
When I removed the the left cat, parts fell out of the inside.
After cleaning with rubbing alcohol, there were 4 spots it burned up or fell out at, so I used High Temp Refractory Cement. Good for 3000*F.

The car only has 49,000 miles on it.

 

Whoa! So the CAT essentially self-destructed. Crazy temperatures!
-Icer