Oil Change Results
 

Still waiting the Blackstone results for this change but wanted to share my results and get some feedback...

RV-9A
O-320-E2D
No air-oil separator on breather
20W-50XC
~30 hours on oil
Used about 1qt in that 30 hours with level kept at 6-6.5 qts.

Prior analysis showed "upper end" (Blackstone comment) corrosion which coincides with limited use while the aircraft sat for sale with limited flying last year. Jug was pulled during pre-buy to look at cam and tappets, which were normal.

I flew aircraft for 45 mins and drained oil. This was an easier than expected, but a little messy pulling screen.

Here's what I observed...

1. Oil was remarkibly clean looking for 30 hours. With the limited burn I would guess this means the upper end is runing tight with limited blow-by.
2. Screen caught a small amount of carbon and what seemed to been some old rubber gasket/seal material. Total...it was an immeasurable amount with no metal
3. Oil filter - Filter media inspected and run over with strong magnet, no metal found
4. Oil filter media washed with mineral spirts and fluid was strained in coffee filter, no metal, and only few small specks of carbon found
5. Strong magnet was placed in jar while washing filter media to pick up anything ferrous. Only a very small amount of ferrous material was found (see picture).
6. The ferrous material collected by the magnet was very fine...like dust, but there was a couple small flecks of metal < 0.5 mm wide and very thin.

Here's some picts filter inspection process and magnet...I want to get some opinions...Tim

This is what the magnet looks like clean...

Long time ago I cut an oil filter open with a hacksaw. Found similar magnetic metal specks.

I didn't use a hacksaw...I hope this is joke and not a reference to my 320 making metal like a hacksaw. :(

I have this filter cutter which works great!



..so is the fine wear metal a bad sign? The metal size is a lot finer than it looks in the picture. It's like the fine paste you get on oil pan magnet on a car engine or transmission. Actually, It was so fine when I wiped it off with a paper towel it soaked into the paper fiber and wouldn't pull out with the magnet. Here's a pict of paper towel...

Also...the coffee filter shows screened material but it's only fibers from cutting the oil filter media no metal was picked up when run over with the magnet.

Absolutely not Tim no intent to reference sorry if misunderstood. That particular cutter were you able to cut the filter top with nipple or you unscrewed the nipple?

I don't have the nipple on my filter...the standard -E2D filter adapter is suppose to take the 48110 filter with a nipple but I have a different filter adapter that takes the 48103 filter without a nipple.

I think this will work with the male thread. I believe they're all 3/4"-16 nipples and the slot in the middle of this filter cutter is 0.80" wide

Tim,
Sounds like thus far you've done everything correctly. Unfortunately, a few years ago I made the dreaded mistake of not having a jug pulled durning the pre-buy & 160hrs later the engine had to be removed due to lots of metal in the filter. It was cam spalling due to limited flying over the past few years. A very expensive mistake on my part.
However, there does not appear to be much metal present in your picture.

Tim,

A little more steel on the magnet than I like to see, but well within Lycoming guidelines. Fly it more, cut another filter.

Opinion worth what you paid for it ;)


Wash jar with a magnet on the lid...very interesting technique. I've been a "cut the element out with a knife and then wash it" guy, but if shaking the intact element in a jar full of solvent effectively shakes loose the filtered debris, it sure looks like a labor saver.

Gentlemen, is this a common procedure and I just missed it? Thoughts about effectiveness?

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.

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

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.

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.

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.

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.

Only Speculation . .
 

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.

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.

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.