Author Topic: OS FP25 muffler tail cone nut - what does it do? (Read 1575 times)

Dennis Toth · « **on:** April 24, 2014, 07:18:50 AM »

Guys,
I was working with my K&B 40 fitting the OS FP25 muffler and wanted to reposition the angle of the exhaust so I started to loosen the rear nut and found it just kept turning without releasing the tail cone. It wouldn't come out just spin. I loosened the front bolt and it released the tail cone and I was able to repostion it where I wanted. I retightened the nose bolt the whole muffler is tight but the tail nut still spins, does anyone know what the tail cone nut does in these mufflers?

Best, DennisT

Andrew Hathaway · « **Reply #1 on:** April 24, 2014, 08:46:22 AM »

It's a jam nut to lock the assembly together. The nut should snug up tight against the cone, if it doesn't it sounds like the bolt or the nut might be stripped.

Paul Smith · « **Reply #2 on:** April 24, 2014, 09:57:50 AM »

Correctomundo.

The long bolt is threaded into the tail cone and the back nut is somewhat redundant. But the combination does a good job of holding the thing together.

Bill Heher · « **Reply #3 on:** May 31, 2014, 07:27:05 PM »

without the nut on the end the screw can vibrate loose. it will eventually unscrew from the outlet end, finally the end of the muffler falls off and your plane will get real loud, and if using muffler pressure it will lean out and start screaming around at max rpm until you get behind it and crash - not that it ever happened to me........

Author Topic: OS FP25 muffler tail cone nut - what does it do? (Read 1575 times)

Dennis Toth

OS FP25 muffler tail cone nut - what does it do?

Andrew Hathaway

Re: OS FP25 muffler tail cone nut - what does it do?

Paul Smith

Re: OS FP25 muffler tail cone nut - what does it do?

Bill Heher

Re: OS FP25 muffler tail cone nut - what does it do?