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Lycoming Exhaust Gaskets

bkervaski

Hellloooooooo!
Testing
I'm mounting my exhaust today. The engine (IO-390) came with 8 copper gasket seals.

I read both that these should be installed in pairs and by themselves. The instructions I found for another engine model said to mount the flat side towards the engine and the "bead" towards the exhaust, conflicting info.

Can someone please clarify how to properly install the 8 copper gaskets for the exhaust?

Thanks!!!
 
This is what Rapco says about their gaskets -

* Be sure that exhaust stack & cylinder flanges are flat
* Install solid gaskets with raised bead facing the exhaust stack flange -- *These may be used in pairs with raised beads interlocked, if desired.
* Torque exhaust nuts to specifications from OEM manual -- Re-Torque after a hot run.

But lots of users prefer the reusable ones -

RAPCOGASKET.jpg


Rapco RA77611
Lyc 77611
Superior SL77611
 
If you have the copper beaded things, I'd hang on to them and use them on the intake side. For the exhaust, grab a set of the blo-proof that Gil illustrated.

Should be an "install and forget" thing for both.
 
Thanks, guys. Got it now. I went down to the local avionics shop and got some of the blo-proof gaskets. :) :eek:
 
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