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So called Penn Yan the said 16 weeks and no new cylinders, everything is overhauled. They want $33600, Zephyr engines said 6 months and wanted $29200. No one has any engines for exchange, looks like this is going to be a waiting game.

Any more ideas?

Could the metal shavings be coming from a cylinder? It would be shame to jettison the engine if all that is needed is a cylinder.

Charles wrote: ↑Fri Apr 01, 2022 7:29 pm I also like everything Mike Busch says about engines, but my 1965-hour engine has started showing a little bit of metal shavings in the filter. Not enough to cause concern to my mechanic, but enough for me so we will get it done in the fall. I got a quote from a very reputable shop here in Canada few months ago for 28.5k CAD (22.7k USD), plus sales taxes.

That could very well be the case Lance. But the way I see it, I'm going to have to do it within a few years anyway and anything I spend to extend it now is unlikely to reduce the overhaul bill significantly when it comes due. Plus at the rate I fly, that's going to be the last one, so from a lifetime spend perspective, it makes no difference to do it now or in a couple of years, and going for the overhaul right away might actually be cheaper overall.

Given that, I figure I might as well indulge with a freshly overhauled engine right away and enjoy the peace of mind that comes with it. Not to mention the wife's opinion on the question!

Charles wrote: ↑Fri Apr 01, 2022 7:29 pm I also like everything Mike Busch says about engines, but my 1965-hour engine has started showing a little bit of metal shavings in the filter. Not enough to cause concern to my mechanic, but enough for me so we will get it done in the fall. I got a quote from a very reputable shop here in Canada few months ago for 28.5k CAD (22.7k USD), plus sales taxes.

Charles, I'd be curious what type of metal was found in the filter. Were the metals magnetic? Did you also have an oil analysis (e.g. Blackstone) performed? The oil analysis would help determine from where the metal was coming (rings, cylinder walls, bearings, etc, etc). All this would be good to know for general info, even though you've decided for an overhaul.
Thanks,
Wayne

Wayne, my last oil analysis dates back to last august. All results were well within the normal range and showed no upward trend on any of the metals analyzed. It came as a surprise to me in last week's annual that there was so much fine metal shavings in the filter. Sadly, I neglected to ask my mechanic to save an oil sample for analysis so I won't know if it has changed.

The shavings are not magnetic. The mechanic thinks it could just have been a cold start (although I have no recollection of having started the engine below freezing without pre-heating). He set a 10-hour time limit on the engine to do another filter inspection. If we find more shavings, we'll schedule the overhaul for the fall. If not, we will accept his assumption but I might still schedule the overhaul nonetheless, for the reason I explained above and which, as a mechanical engineer who worked for the 2 largest aircraft engine manufacturers, I will readily admit to not entirely being rational.

My 2003 engine is at 1950 hrs and runs great. The oil consumption has been steady since I bought it 3 years ago at 7 hrs per quart. The oil analysis reports have been great and no problems have been found on the borescope inspections. I'm flying about 100 hrs per year. I use the $375 per year Saavy QA program to consult with someone if I have a question and they have been great to work with. I'm waiting for an indication that I need an overhaul, but will probably intervene a little early because of the current delays. A DA20 in a hanger near me has been without an engine for the 5 months waiting for an overhaul. I'm not sure where they sent it. It's nice to read how others are thinking about their overhauls.

I'm at 2400 hours and running strong!

Seems I jinxed myself my commenting on this thread. Just heard back from SouthTec and they found significant magnetic shavings in my filter. Iron has been creeping up in my oil analysis over the past year and despite no shavings in the past year the filter they just pulled, with only 25 hours, was filled with them. Still waiting on the latest oil analysis to come back but I sure hope I'm not going to be grounded for the rest of the year.

mhoran wrote: ↑Thu May 12, 2022 6:43 pm Seems I jinxed myself my commenting on this thread. Just heard back from SouthTec and they found significant magnetic shavings in my filter. Iron has been creeping up in my oil analysis over the past year and despite no shavings in the past year the filter they just pulled, with only 25 hours, was filled with them. Still waiting on the latest oil analysis to come back but I sure hope I'm not going to be grounded for the rest of the year.

This is almost certainly cam/lifter material. The other possible source would be cylinders but compression check and borescope can be used to eliminate the latter as a possibility, but the cam deal is much trickier to check without at least pulling a cylinder or two.

Compressions were fine though they noted bleeding past the valves and rings. Not surprising given the issues I've had with blowby. I was fine dealing with the mess but the shavings are far more concerning.

I was hoping it'd be something simple like the rings but with the valves leaking it seems at least one cylinder may be bad. Not sure how much sense it makes to do a top at 1960 hours if the cams might be going. Seems like I'm going to be down for a while. Sigh.

Pictures (seems the forum still has some size limit; it rejected these):
https://i.matthoran.com/oC_cpSIVZX4.jpg
https://i.matthoran.com/WTC0-0EJqqc.jpg