Exhaust How to seal an exhaust?

[Captain Rainmaker]

So a while back I bought and installed the Sick Bike Parts expansion chamber, and I'm having a hard time getting it to seal properly. It's not leaking gas and making a horrible noise, but it is seeping quite a lot of oil.

The parts stackup consists of the header flange, a series of copper pipe fittings, the J-pipe, and the expansion muffler. The kit came with some silicone couplers to seal between the copper fittings and the J-pipe, but they were too small to fit over the J-pipe and the ones I could get to fit aren't really doing much to stop the oil seepage. I also tried some high-temp JB Weld but apparently it wasn't high-temp enough and is starting to break down. What else is out there that I can try?

(I'm running at 16:1 right now to break in a new jug, so that probably isn't helping the situation. Still, if there's a better, cleaner, and more presentable way to fix this, I'd like to know.)

 

[Wrench]

Kinda sounds like you need the correct size silicone couplers
But you can try Prematex Copper high temp 700*F silicone gasket maker. People use it for exhaust gaskets and say it works

 

[Captain Rainmaker]

Paid a visit to the usual scumbags and bought a tube of VersaChem exhaust sealer paste. So far it's working great.

Interestingly, I caked the exhaust in the stuff, not caring about apperances as long as it sealed, and after a few days of puttering around, the excess simply hardened up and chipped off, leaving my pipe looking very clean. There's still a tiny amount of seepage, but no audible leaks. I think I can live with that.