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High nickel in oil?


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This is my third oil sample result in 150 hours and my nickel levels are still high. Are the valve guides the only thing that would be indicative of this? I'm thinking I should be #4 (see times below). Maybe I should be planning on swapping it out here shortly?

180hp O-360-A1D,
2100SMOH
Crank & Cam - Approx 900 hrs
Cyls 1, 2, & 3- Approx 500 hours
Cyl 4- 2100hrs

 

engine.JPG

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Although I'm not sure of other possibilities, I'd bet that you do have an exhaust valve guide that is going bad.    A careful borescope exam of the exhaust valve faces should tell you which one it is. 

It's happened to me twice so far.  The times on the cylinders may not correlate with which one is the offender.  In one of my cases, there was also a hiss at the exhaust when pulling the prop through the compression stroke for that cylinder. The leak was also audible at subsequent static compression check, but the compression number was still in the 70s.  In the other case, the compression on that cylinder turned out to be low.  In both cases, the guide was out of spec on wobble test with the valve covers  off. 

As a quick diagnostic that an owner can do easily, I'd say borescope exam through the bottom plug hole is a pretty powerful way to anticipate an A&Ps findings.

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3 hours ago, Tony Starke said:

984E3FB4-F93F-4103-9AC1-02778F964EF3.thumb.png.61fa6bd70cd5a1c864af42d417f63776.pngAlex, any chance you have nickel cylinders? These values are pretty close to mine which seems to be normal for nickel cylinders.

I have nickel cylinders as well, but my nickel numbers are quite a bit lower than yours.  My cylinders have a similar time in service to your engine.

8ABECD85-1566-4771-8DE8-6E4986497458.jpeg

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36 minutes ago, Raptor05121 said:

Sorry, I checked my cylinders which #1-3 are silver (steel) and #4 is orange, which if my research is correct, should be steel with 0.010" overbore

Mine have a single silver stripe as well. I believe orange is chrome. You might consider calling L.J. At Zephyr Engines for clarification.

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1 hour ago, gsxrpilot said:

A wobbly valve can also show up on engine monitor data as a spiky EGT line. If you are uploading data to Savvy Analysis regularly, they will notify you if their algorithm identifies a wobbly valve.

I do upload to them....never did ask them what capture rate they require for that.  My JPI900 snapshots every 6 seconds I think as factory default but I can make it quicker..not sure if I want to mess around with that

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31 minutes ago, Jim Peace said:

I do upload to them....never did ask them what capture rate they require for that.  My JPI900 snapshots every 6 seconds I think as factory default but I can make it quicker..not sure if I want to mess around with that

@kortopates is the expert on this. But I think it's a great service to have. 

I was going to request someone look at some of my data to check for wobbly valves. That's when I discovered that they run all flight data I upload through algorithms looking for that very thing and will notify me if it pops up. I don't have to do anything but fly and upload the data.

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2 hours ago, gsxrpilot said:

A wobbly valve can also show up on engine monitor data as a spiky EGT line. If you are uploading data to Savvy Analysis regularly, they will notify you if their algorithm identifies a wobbly valve.

True, but it's worth noting that this spiky pattern only shows up pretty close to the time the valve finally fails.  I've also never gotten a clear answer on whether it shows up  before failure in every case - so looking regularly but not seeing it may give false security.  Certainly a guide can deteriorate for a long time before it ever shows this pattern.  Neither of the two jugs I pulled for trashed exhaust guides had this EGT pattern or identified the offending cylinder in any other way in the engine monitor data. But in both cases I could feel the extra slop in the valve guide by hand once the jug was off after seeing the tell tale crescent at the edge of the valve face.  

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I had two exhaust valve guides go with great looking oil analysis (chrome cylinders).  I did see the telltale egt pattern on graph from my jpi 930 in 6” capture.  Also noticed slight loss of power (speed) about 5 minutes after leaning for cruise.  On the graph, leaning looked normal, then couple minutes later, #3 egt rose about 75 degrees (which is higher than its original peak).  It was pretty stable there.  Repeated this several times as I reaccomplished leaning lop.  Mechanic did wobble test and found both 1 and 3 bad.  Interesting, he borescoped first and they looked ok, but he was pretty sure from the engine data already...

Ill be interested to see what you find as I ise Blackstone as well.  Hasn’t ever shown me anything but makes me feel better.

Edited by Ragsf15e
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