Oil Change Results

[BillL]

Originally Posted by avrojockey

Dan...I'm not sure if this is a common technique and maybe the amount I'm getting is from my abnormal technique. I cut open filter and visually inspected and found only a few very small (< 0.5mm) pieces of carbon. Visually the filter medium was very clean. Even after washing and letting it dry out in the sun I was only able to find a couple extra very small specks of carbon and still no metal of any variety.

When washing the filter medium in the mason jar I used a neodymium magnet, which is the strongest type of permanent magnet, and I washed it 4 times and strained fluid in at the coffee filter.

I want to reiterate that the picture of the coated magnet makes the particles look larger than they are because the magnetic field is making them stand up on one another. This wear metal is so fine I don't think the coffee filter would have even caught it...finer than graphite lubricating power.

I'll post my Blackstone results when I get them.

Post the early analyses too. That would help. Absolute numbers (PPM) of metals are very helpful for an internal wear evaluation.

BTW, I learned how to inspect filters from a lab with 110 operating test cells. They cut open, remove filter paper, then laid it on a 1/2 thick layer of paper towels. Then wet with stansiol solvent (i use mineral spirits) then lay a a big piece of steel on the top to press into the towel. Come back a couple of hours later and inspect.

I do much the same, use Viva paper towels on top and bottom, 5 lbs of 1/2 steel bars, and inspect the next day, it is bone dry and shows shiny particles easily.

All of this above is correlated with oil analysis results.

Your method is interesting, and not to imply it is wrong.

To OP: Any repeated high Fe content in well stirred oil would be a call for deeper inspection. It could be a result of fine rust formed on gears and now is continually eating into the teeth. That fine material is an abrasive slurry to oil passages.

Any field opening of the engine can yield a jump in wear metals for a period.

A particle size analysis using ISO terminology would be helpful if diagnosis needs to continue. Hopefully, it will all diminish with regular use - continue your short oil change periods to establish a trend sooner.

[avrojockey]

Originally Posted by BillL

Post the early analyses too. That would help.

I'll post the prior analysis...its the only record I have. Hoping for a decrease in PPM.

Originally Posted by BillL

Any field opening of the engine can yield a jump in wear metals for a period.

Interesting...I was wondering if a cylinder removal and reinstall of the same cylinder/piston/rings can have a small "wear-in" effect, but not as much as newly installed jug.

Originally Posted by BillL

Hopefully, it will all diminish with regular use - continue your short oil change periods to establish a trend sooner.

Yea...I think I'm leaning towards SI 1492 guidance. According to it I could stay with normal 50 hour interval but certainly want to catch something earlier if there's a problem.

[DanH]

Originally Posted by BillL

BTW, I learned how to inspect filters from a lab with 110 operating test cells. They cut open, remove filter paper, then laid it on a 1/2 thick layer of paper towels. Then wet with stansiol solvent (i use mineral spirits) then lay a a big piece of steel on the top to press into the towel. Come back a couple of hours later and inspect.

So the intent with this technique is to remove all the oil, leaving the debris more evident on the filter paper?

[BillL]

Originally Posted by DanH

So the intent with this technique is to remove all the oil, leaving the debris more evident on the filter paper?

Yes, that's the idea.

The shake and strain method seems to get the embedded particles better, but one would need a baseline. I would think the suspended particle analysis could pick that up, but only data can tell us, thus previous analysis results query.

[avrojockey]

Originally Posted by BillL

The shake and strain method seems to get the embedded particles better, but one would need a baseline.

That's what I'm wondering about the fuzz on my magnet. I hoping these particles are normal wear...its just the method I used that made them so evident.

[BillL]

Originally Posted by avrojockey

That's what I'm wondering about the fuzz on my magnet. I hoping these particles are normal wear...its just the method I used that made them so evident.

Hard to say, Tim. I have no hard experience with that method with which to correlate, but, I think not from a normally operating engine out of break-in. It may be normal generation but just accelerated due to sitting. Lots of speculation, and few hard answers at this point. It could just be still cleaning the insides from some light rust. Was the barrel cherry honed and washed prior to reassembly?

Are you familiar with the guidelines? Fly every 30 days, fly for about an hour at oil temps around 180F to prevent accumulation of water in the oil, use Camguard if desired to leave sitting longer than 30 days. Or use a crankcase dryer to drop the case volume dew point. Even taking a mattress inflator and blowing into the dipstick tube for 3-5 min will clear the crankcase and drop humidity to ambient levels, a 95% reduction. These are longer term things to keep in mind, but for now the oil analyses will be helpful along with the next oil change. Nothing here to confirm a rapidly progressing failure, so just fly and check.

[avrojockey]

Thanks for all the feedback folks!

The good news is I fly almost weekly for 2.5 hours+ now, and I'm using Camguard. I'll stay with a 25 hr interval until I can identify a trend using my techniques, and I will keep all updated on my findings for review and post the last two oil analysis soon.

[avrojockey]

Analysis done...

Oil analysis looks much better then it did during my pre-buy . Obviously, the 9/19 oil analysis looked a little scary, but that's one of reasons we pulled a jug in the pre-buy.

It's good to see things are cleaning up. Looks like I may go back to a normal oil change interval.