Updated Continental 79-01 Connecting Rod Piston bushings ICA

[Learjetter]

FYI

MEL-79-01 - Oil - Transmittal of Continental Aerospace Technologies CSB07-1A Connecting Rod Piston Pin Bushing Inspection (Models: Multi Engine A/C) Compliance: M - Date: 04/21/2021

PS: does anyone use a shorty-quick drain plug mechanism on the front engine? Any recommendations for magnetic quick drains for either engine?

[JAG]

Great quick drain for front engine - is STC'ed.
Jeff

https://bogertaviation.com/collectio...024nm-complete

[TomM]

I have the Saf-air quick drain installed on the front engine. The only requirement is that when installed the gear has to be retracted and verify that there is a specific gap between the plug and the landing gear. I had plenty of room on mine. It is the F62 model that fits our engines

https://www.saf-air.com/products/oil...eoildrainvalve

[mshac]

I'm sure the STC'ed ones are fine, but the Service Manual has a big warning saying not to use a quick drain as it could interfere with the nose gear transit. It looks like a "short" quick drain will work, but not a normal one. YMMV.

Here is the correct one for our Skymasters for $115 from Wag-Aero: https://www.wagaero.com/low-profile-...es-p-nf65.html

I've attached the section from the manual.

[JAG]

My recommendation for the STC'ed Bogert quick drain valve does not interfere with the nose gear. I am an experienced mechanic. I have installed one on my C337A, swung the gear and verified the clearance. It is not an "external" quick drain, you have to have a tool that pushes up "internally".

Thought I would clarify - I don't make recommendations on this site that I have not researched or validated.

Jeff

[mshac]

JAG, in looking at the drain valve, it appears that the threads are higher than the bottom of the oil pan, which would create a situation whereby the last bit of oil never gets drained. This is why we are told not to use oil suckers like boats and cars use to change oil, because it may not get it all out, leaving sludge and metal particles in the oil pan.

My perception may be incorrect about the quick-drain valves, any comments?

[JAG]

MSHAC,
Your perception may well be correct, but my guess is that the amount left behind is going to be a very small amount. I have not measured the threads of the oil pan to be able to determine how much may get left over, but if they are designed properly, they should not leave any behind.

That being said - the design of the IO-360 oil pan does locate the drain in such a way that is very effective in draining, and if there was small amount that was not drained, it would likely be in the range of only a tablespoon or two. In my experience, this is completely acceptable, and still way more effective than using the suction device (unless of course, you can guarantee that the suction device is at the bottom of the sump). There will always be that little bit of sludge/carbon that will accumulate in a pan (in my opinion), and the net benefit of the quick drain is still far greater than the mess the old way of draining the oil can make. Of course, I say all this with the full expectation that everyone has oil filter systems installed, is changing the oil when it is hot (and not sitting long) and is changing their oil at proper intervals for how they are operating their aircraft.

If anyone has an oil pan on the shelf or next time they remove a plug, could measure the depth of the threads - we could validate approximately how effective the quick drains are.

Jeff

P.S. As a side note, on a different engine OEM, I once had a cam shaft crap a bearing into my oil pan. I discovered this after investigating why my oil pressure had a change of about 5 PSI (but still well within limits). I had a new gasket for the pan, and thought at the time I will have a look at the screen on the oil pump pick up while have it off. As I walked the oil pan over to the bench, I noted large pieces of material in my oil pan and thought to myself...this is going to be expensive. Anyway, the point is, metal deposits may or may not come out of the drain, regardless of the drain type, but certainly less likely with a quick drain. However, the most effective tools to mitigating that or any other particulate issue in the oil, is a filter.