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Sludge and flaking

Vlad

Well Known Member
My engine passed mid time a year ago and it was time to change leaking valve covers gaskets. When I removed the covers I noticed a rather thick layer of a reddish colored sludge. What caused that? Disintegrated cork? Rust from not very often used engine guts? :eek: Bob please take a look.









Also noticed flaking Lycoming gray on intake flanges.







Dumped couple of intake hoses but couldn't find right spring clamps for those. Reused old hose clamps. If anybody has right size spring clamps handy please post below.







My maintenance shop. Who got bigger?










First 20 hours on red gaskets they look good and don't leak.



 
Hey Buddy, you have to get some fancy paint for those valve covers! $5 worth of paint will make your engine look like a $$$$$!
 
Bob, do you use The Lycoming oil additive when you use the Phillips X/C or is it straight up?
 
No I'm not a believer in additives and won't be until there is good data to indicate any of them work. I'm talking about aviation-specific additives. I have seen the varnish so thick from Aeroshell that I was able to peel it off with a fingernail. Is it harmful? I don't think so.
 
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Wow, are you saying you haven't pulled the rocker covers for a 1000 hours?

I love those red gaskets - the don't leave a bunch of cork **** all over everything. I change them out first thing when the engine comes back from a build.
 
Wow, are you saying you haven't pulled the rocker covers for a 1000 hours?

I love those red gaskets - the don't leave a bunch of cork **** all over everything. I change them out first thing when the engine comes back from a build.

Cork gaskets have nothing to do with Aeroshell varnish...the entire inside of an engine fed with Aeroshell oil will look like that. Not so with Phillips X/C.
 
Cork gaskets have nothing to do with Aeroshell varnish...the entire inside of an engine fed with Aeroshell oil will look like that. Not so with Phillips X/C.

All I have ever run is AeroShell in the airplanes I have owned, and yes I have noticed the varnish but thought it was due to cylinder head temps after shut down. Maybe I should use Phillips X/C in my factory new IO-390 on the -14A.
 
All I have ever run is AeroShell in the airplanes I have owned, and yes I have noticed the varnish but thought it was due to cylinder head temps after shut down. Maybe I should use Phillips X/C in my factory new IO-390 on the -14A.

Lycoming guy at the AOPA forum we had here a few weeks ago said Aeroshell is the stuff to use. Manufactured with all the additives Lycoming recommends.

When asked about camguard etc, he said something like, "If any of that stuff made our engines better, don't you think we'd put it in Aeroshell? It isn't good business for our engines to fail, y'know."

He also claimed that no Lycoming engine with roller tappets has ever suffered cam spalling, so that's a bit of a big deal I guess.

- mark
 
We just pulled the valve cover on a engine with 800 hours run on aeroshell and it was very clean and did not look like that. We have 800 hours on the engine. Why would they be different?

George
 
We just pulled the valve cover on a engine with 800 hours run on aeroshell and it was very clean and did not look like that. We have 800 hours on the engine. Why would they be different?

George

Which Aeroshell? In all the cases I've seen its been 100W, 100W plus and 15W50, but not ran on one uniquely the whole time. Perhaps the antiwear additive has something to do with this.
 
For this running Asroshell, it would be nice if you stated which Aeroshell you are using. The 100W is straight oil with few or no additives, the 100W Plus has the additives and the 15W-50 (I think that's the right number) is semi-synthetic.

The Lycoming guy said they use Aeroshell, then said, "don't you think we'd put it in Aeroshell," talking about CamGuard? Is there a relationship between Lycoming and Aeroshell?
 
I ran AeroShell 15W50 exclusively in the Cherokee 180 we had for over eight years. Since overhaul that engine only used 100W one oil change when I ran out of the 15W50 and it developed some light varnishing under the valve covers and around the valve springs. I had the cylinders off once and there was a slight film of varnish on the rods and crank but the case was clean.
 
The Lycoming guy said they use Aeroshell, then said, "don't you think we'd put it in Aeroshell," talking about CamGuard? Is there a relationship between Lycoming and Aeroshell?

Yes. 100W Plus is a bit of a joint venture.

- mark
 
Yes. 100W Plus is a bit of a joint venture.

What is your source for this information?
Historical posts by the developer of Camguard on this forum (user N761tj) make it pretty clear this is not true, as he recommends shell 100w but NOT 100 plus (claims it attacks seals)
 
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