M20J Exhaust Manifold Gaskets

[madreg98]

I have a 1988 M20J with 500 hrs following a factory reman.  Had a conversation with my on-field repair shop who does the annual and they said that every two years they inspect the exhaust manifold gaskets with the expectation of replacing them.  Is this typical?

[A64Pilot]

Maybe, I use blo-proof gaskets and they don’t blow, just as the name says, or I’ve not had one yet, nothing is perfect but I suspect that they do last longer.

I don’t know what’s on my J though as I’ve not yet had to pull the exhaust, I should be able to tell by looking as the blo-proof ones are thick, but I have not looked.

https://www.aircraftspruce.com/catalog/eppages/bloproofehaustgaskets.php

Ones I have used are I believe spiral wound, I can’t attest as to what’s best

https://www.aircraftspruce.com/catalog/eppages/rapcoexhaustgas.php

[N201MKTurbo]

I think the mineral fiber gaskets seal better. The blow proof gaskets last longer. The thin copper gaskets are worthless. 
 

I have never replaced them unless I have removed the exhaust for a reason.

[PT20J]

Lycoming ships engines with the crappy beaded gaskets. I threw them out and used the spiral wound (no blow) gaskets when we installed the rebuilt engine. See Lycoming SI 1204D.

[Beard]

I have owned my 1984 J for 14 years and have flown it 700 hours and have had no issues. I have replaced two jugs and I believe they came with new gaskets, but I did not to my knowledge replace the other ones. 

[laytonl]

I don’t change the gaskets unless needed, but I do periodically change the nuts (every 4 years or so).  Lee

[Costa Leite]