jetdriven

That’s the part I don’t understand, Why have gain settings at all,l?? just program the controller to have the gain setting value hardwired in, gain settings are meant to be tweaked for the specific airframe combinations. Seems like a copout on the manufacturers part.

You sound like a very thorough troubleshooter, and it seems like your oil pressure transducer is the issue. Do you have a JPI that shows oil pressure as well? That is something You can cross reference.

That’s part of the problem, the Naca duct is inside the prop arc and exposed to the sun. And different probes will vary different amounts because of this. I know for certain Davtron says to mount the probe outside the prop arc and in the shade. I think JPI does too.

Just take the I-10 corridor, and ask the controller for flight following through the Corridor. Also, pick an odd altitude number like 14 or 1600 because everybody else uses even numbers around there. General etiquette as you stay on the right side of the highway when you have room from the class B.

I think you meant the speed increases in a spiral, and that’s the problem…..the plane is so clean if you don’t get the lift vector pointed up and pull 3 Gs on it you’re gonna go through Vne pretty far.

I think you meant the speed increases in a spiral, and that’s the problem…..the plane is so clean if you don’t get the lift vector pointed up and pull 3 Gs on it you’re gonna go through Vne pretty far.

I wholeheartedly endorse stalling them during training…but inadvertent stalls at low altitude never end up well. Hence the normal operation part, just don’t allow that to be something that develops.

I’ve seen a few of these Doghouse M20C’s and they all run hot. Add the power flow makes it even worse. You’re making more power from the engine without an associated increase in full throttle fuel flow. Turning the carb up helps. I suspect that relocating the oil cooler helps. But 420 at 1000’ seems to be the norm. Powerflow seems to make that worse. I’ve got a 1968 O-320 Cardinal doing the same thing. Now we’re sending the carb off to get the main jet richened up ans gonna make the baffling 100% airtight. It will help but it won’t run cool

Google the tail number

Its about it 1/16 of an inch, but even at 1/8 of an inch how much oil quantity error are we talking about here?

Any damage history ?

You can also put an o-ring on it. Then it stayed fixed for years

Interestingly that engine running without oil pressure video, after two minutes the RPM started coming down pretty seriously.

You can always punch a hole in it and fill it with oil carefully and then screw a drywall screw into the hole to seal it.

Tempest has approval now you can use a 48108 filter in place of the 48109. They are now interchangeable.

Mike's plane is in my shop right now for its second annual here. He and I had the same experience when we both put factory engines on our planes 7 years ago, and putting Bendix mags on it and turning it up made a big difference.

There is some speculation that the roller cam engine made more power than rated, so they effectively de-rated the engine by changing the cam profile or advancing the camshaft. But a roller cam engine running at 20° is quite noticeably slower than a A3B6D engine running at 25 degrees. Actually, around 23-24° is the best timing for these roller engines.

I agree, it's magical thinking to think that 20° of timing makes the same power as 25. When we bought our plane we noted it was a complete dog on takeoff and climb and cruise, but we figured there was probably some optimization or it was a tired engine. Come to find out the dual magneto at 20° which is not even allowed, putting it back where it was supposed to be made us 5 kn in cruise and it would actually run lean of peak whereas before the speed would fall off right proportionally with fuel flow. for your hot running engine, fix the cooling deficiency, instead of covering it up with the Band-Aid by derating your engine

i dont think aerodynamics works that way in this instance. The prop is still pulling the airplane forward. At 2000 RPM, all else equal, its less HP at the crank which aids descent.

If it were me I would eat the 20k and labor. You may be able to disassemble it and swap the bearings, hone it and put new rings and put it back together yourself for a lot less than that. You gotta pay the engine shop and the labor to r/r it, but it’s probably better than getting cancelled for mx shop insurance. There’s only two people writing shop policies, and one of them doesn’t understand the type of work shops do, and they cost more also. and I’d get the plane into a different LLC today. If someone has a claim against your shop, your 250k plane is at risk for anything above policy limits.

It looked like fluctuating oil pressure for ten minutes. Then a five minute flight where the oil pressure did go to zero. Then it threw a rod. It trended down to zero at some point cut it wasn’t likely at zero the entire 5-minute flight. We don’t know exactly when the damage was done, either.

I’m just some guy on the Internet. You can have the mechanic who puts his airplane back together to call Lycoming and get their take on the subject, then analyze the data that it ran for two minutes without oil pressure, and then ask him to return it to service and all of the liability that incurs as well. It’s like a prop strike, it’s probably OK but you really don’t know.

Lycoming can explain it better than I can but any engine ran under 55 psi of oil they say the hydrodynamic wedge oil protection film is lost and the only way to verify it is to tear it down. https://www.lycoming.com/sites/default/files/Action to Take If Loss of Oil Pressure.pdf

You’re gonna have to tear it down. I’d ask the oil filter mfr to pay the bill.