Cylinder Pics. Too much oil?

[andyrv]

Not the best pics but here are all 4 cylinders. Superior XP-IO-360 at 770 hours. My question is the amount of oil in the bottom of 3 of the 4 cylinders. I seem to be going through oil at a faster rate these days. Comments?

Thanks,
Andy

[Mike S]

Pretty sure you got some problems for sure. Personal opinion here is that I would not fly with that on my plane. I have borrowed the worse looking photo as an example, but all show some issues.

Not only do I see score marks, but the crown and also the edge of the piston appears to be damaged like it was pounded by something floating around in the cylinder----broken ring maybe?

Also, the cross hatch is totally worn away.



Are you running without an oil filter------or air filter??

[andyrv]

Another view of the same cylinder. Dental cam is hard to work with but here you can see the crosshatching in the cylinder. Pretty sure the ugly looking stuff on the pistons is lead deposits being brightened and magnified by the camera. Yes to both oil and air filter. Last annual 100 hours ago and all 4 76-78 out of 80 on compression.

[Mike S]

Originally Posted by andyrv

Another view of the same cylinder. Dental cam is hard to work with

Wow, hard to work with is quite an understatement-----that looks like a different cylinder, not just a different view of the same one.

Perhaps you should have a mechanic with an actual borescope take a look at it??

[walkman]

Please see the thread about what happened to my Superior XP 360 with 900 hours in this same section of the forum.

[DanH]

Originally Posted by walkman

Please see the thread about what happened to my Superior XP 360 with 900 hours in this same section of the forum.

Yeah, right. You never did tell us the rest of the story.

[walkman]

Originally Posted by DanH

Yeah, right. You never did tell us the rest of the story.

Yes, I'm been hammered with an immense amount of work in the real world as well as with the airplane, in addition to studying for and passing (91%) the commercial written.

I never did determine what caused the piston damage, I have a number of theories and no definitive answer.

Ultimately I sold the core to someone who wants to rebuild it, and have purchased a brand new engine which I am installing now. I hope to start it for the first time tomorrow and fly this weekend.

I plan on doing a write up on the engine I chose, the trials and tribulations of the installation, and my experienced with both the motor and the vendor once I get over this hump.

Here are the related threads:
http://www.vansairforce.com/communit...d.php?t=116604
http://www.vansairforce.com/communit...d.php?t=117119
http://www.vansairforce.com/communit...d.php?t=117119
http://www.vansairforce.com/communit...d.php?t=117603

[Mike H]

Originally Posted by DanH

Yeah, right. You never did tell us the rest of the story.

Could It have been an oil starvation/pressure loss issue due to negative G acro?

[DanBaier]

... the amount of oil in the bottom of 3 of the 4 cylinders....

I've seen that much oil collect at the bottom of a cylinder before in an engine that was running normally and not consuming a large amount of oil.

You could have some scoring, but my experience with the dental cameras is that they tend to magnify the appearance of problems that aren't really there.

I'm a long way from saying everything is okay - if you have doubts, ask an experienced mechanic familiar with lycoming engines to look at it first hand. I think the photos, good as they are, lack the detail to make a good call.

One thing you mention that is really hard to see and is potentially a concern is the edge of the pistons - the potential for heat or other damage.

Dan

[Weasel]

I agree with Dan. The amount of oil looks normal to what I have seen.