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  #1  
Old 09-17-2019, 11:05 AM
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avrojockey avrojockey is offline
 
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Default Is this an Exhaust Leak?

O-320-A1A EXHAUST PICTURE

Referencing linked picture above...What say ye concerning the rust color on the head near the exhaust flange and around the plug well?

It looks to me like a exhaust leak but isn't the typical white color. The other thing I notice is the flange studs...doesn't look like those nuts have come off in awhile which means the exhaust hasn't been removed for inspection.

Last edited by avrojockey : 09-17-2019 at 11:25 AM.
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  #2  
Old 09-17-2019, 11:32 AM
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Possible crack in the head between the exhaust port and spark plug hole?
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  #3  
Old 09-17-2019, 12:43 PM
xblueh2o xblueh2o is offline
 
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Easy enough to test. Pull the plug and do a compression check.
If it is a leak/crack it will show itself instantly.
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  #4  
Old 09-17-2019, 12:47 PM
lr172 lr172 is offline
 
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Typical signs of exhaust leak are a matte, dark black staining/coating. Rust is something different.
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  #5  
Old 09-17-2019, 05:45 PM
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What is above the cylinder in that area?
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  #6  
Old 09-17-2019, 07:40 PM
Ash Ash is offline
 
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Quote:
Originally Posted by xblueh2o View Post
Easy enough to test. Pull the plug and do a compression check.
If it is a leak/crack it will show itself instantly.

Not necessarily true. If the crack is between the exhaust valve and the exhaust manifold, a compression check will not reveal a crack/leak in that area. We found that this past week on our #2 cylinder on our Warrior. It compression tested at 76lbs, but a cracked cylinder in the exhaust port was found.
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  #7  
Old 09-18-2019, 06:41 AM
rvsxer rvsxer is offline
 
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Quote:
Originally Posted by lr172 View Post
Typical signs of exhaust leak are a matte, dark black staining/coating. Rust is something different.
Every exhaust leak I've seen showed as a white or light tan coating. If it's black you are too rich at idle.
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  #8  
Old 09-18-2019, 09:09 AM
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avrojockey avrojockey is offline
 
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Quote:
Originally Posted by fl-mike View Post
What is above the cylinder in that area?
There's nothing mounted on or above the head that would be causing the discoloration.
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  #9  
Old 09-18-2019, 09:23 AM
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snopercod snopercod is offline
 
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The source of those rust-colored deposits has to be steel, so that pretty much narrows down the source. If it were my plane, I would suspect that exhaust gasket first. Good luck breaking that exhaust nut free
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  #10  
Old 09-18-2019, 10:39 AM
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Quote:
Originally Posted by avrojockey View Post
There's nothing mounted on or above the head that would be causing the discoloration.
what color is your baffle material?
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