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Piston head borescope question

TCONROY

Well Known Member
Been flying for 7 years and have about 350hrs on the engine, which was a brand new Lycoming YIO-360-M1B purchased through Van's. I've done the condition inspection each year, following a very detailed and thorough checklist.
I purchased a USB camera and for the first time was able to snap some pics of my piston heads.

I don't really know what I'm looking at here, so looking for some advice and comments on whether the discoloration and build-up is normal. Thanks!

#1
Cyl-1.jpg



#2
Cyl-2.jpg



#3
Cyl-3.jpg



#4 Pic 1
Cyl-4-P1.jpg



#4 Pic 2
Cyl-4-P2.jpg



Thanks!
 
I don’t lose sleep over how ugly the piston tops get.. the carbon is like the ceramic coating that people spend a lot of money on.. and you got it for free! What you want to do is see the valves.. does your borescope have a button to bend the head 180?
 
Lead Deposits

If I'm not mistaken what you are seeing is lead deposits which are gold to silver in color on most bore scopes. Most scopes don't have very good color rendition which has to be taken into account when looking in the cylinder. My understanding is that lead deposits are not an issue.

Regardless, for some good information on how to know when a valve is going bad, search for Anatomy of a Valve Failure on the AOPA.org site. I have a full sized print of the chart in a frame in my hangar for reference. Feel free to call if I can be of any help.
 
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Exhaust valve and cyl walls are the sports to look at also, but these look like normal cyl heads, carbon build up etc.. You want to see cross hatching in the cyl walls with even wear, and symmetrical “bulls eye” patterns on exhaust valves. AOPA and Mike Busch have some great articles and books on the subject.
 
Search Youtube for Mike B's webinar on valves and another on cylinders. LOTS of great info, as long as you can stand the slow pace in his talks. From your photos, all looks good, but as other have said the real area to look at are the valves. That plus a look at the cylinder walls.
 
Thanks all! Helps me rest a little easier. I will look into Mike's webinar regarding anatomy of a valve. I've seen some of his talks and he is truly a genius and very helpful to our community.
 
I too just got a borescope and was at first surprised to see that build up as it looked just like yours. Thankfully the exhaust valves look good! Pretty sure this is normal. I invested in an articulating scope which is great!
 
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