The International Cessna^® 170 Association

I just installed a new #3 cylinder on my C-145. Unfortunately after I reinstalled the exhaust “riser” it doesn’t fit up with the muffler. I tried flipping the riser 180 degrees, but that lined up worse. Any suggestions?

are you using the same type of exhaust ruser stack gasket on all three risers? Have you considered doubling up the riser gaskets?

johneeb wrote:are you using the same type of exhaust ruser stack gasket on all three risers? Have you considered doubling up the riser gaskets?

I am using the same kind (blow proof). I should clarify the picture that the length is okay, but the offset is off.

Just curious if you’ve tightened the risers to the cylinders before fitting the muffler. I went through this recently…had to loosely install the risers and exhaust gaskets then fit the muffler to the risers before tightening the risers further. Long cotter pins were helpful in keeping the gaskets in place during the initial installation.

darhymes wrote:Just curious if you’ve tightened the risers to the cylinders before fitting the muffler. I went through this recently…had to loosely install the risers and exhaust gaskets then fit the muffler to the risers before tightening the risers further. Long cotter pins were helpful in keeping the gaskets in place during the initial installation.

I had tightened the risers before fitting the muffler. I've had the mufflers off a couple times in the past for other engine work and was able to re-install. I think you are right about my next step. I'll attempt to loosen them, fit the muffler, and then torque the exhaust riser nuts. I guess introducing the new cylinder was enough to cause it not to fit right back up.

Barely loosening the exhaust risers and attaching the muffler and clamps first and then torquing the exhaust riser nuts worked just fine. My A&P and I were happy with how it came out and will be watching closely for any exhaust leaks.

Thanks!
Doug