Pilot had his airplanengine rebuilt. Shipped back and installed. Why ZERO oil pressure?

Pilot provided special aviation break-in oil to the factory.
After rebuild, he watched engine run perfectly athe factory.

He and friends installed thengine in the airplane and connected all sensors.
After start-up, oil pressure gauge read zero.

Tried to discover the oil monitoring system problem.
Engine oil was drained before shipping.
$65,000 mistake.

I would never expect a crate engine to come filled with oil. What kind of a maroon would think that’s the case with an aviation engine?


If it was less than 15 seconds or so out of oil it’s probably okay.

It is amazing how people will go to the trouble to have a new engine installed and not check the oil before startup. I went through a situation with a local shop that basically ruined an engine in my truck. They went to the trouble to REPLACE the oil pressure sender at a price of several hundred dollars only to not check and see if there was actual oil pressure or oil in the engine. The oil light was on both before and after the work and somehow that seemed OK to them. They had installed the wrong dipstick as well which was showing the engine was full when it only had about half a quart in it. They claimed it was my fault as I never drained the fresh fill of oil out completely to see how much oil was actually in the engine. I paid a layer a couple hundred dollars and he said I had a case but with the time and headache spent recovering some money, it probably wouldn’t be worth it.

Interestingly the Ford Motorcraft engine that came was a complete long block from the factory with a fill of oil and a filter installed. The shop that installed this engine did actually check to see if there was oil in the engine and at the proper level when they installed it.

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Pilots are big on check lists. Here’s the one I followed before every flight when taking my lessons, years ago. Note the second to last one.


Famous last words at 10,000 ft.


And that’s why I think it’s a fake story.

Not fake.
Had I been there, my OCD would have made me check the oil.
(Frustrated that our 2021 RX350’s transmission fluid was changed this morning and I cannot check it.)

Omission caused by thexcitement of getting his rebuilt engine back with oil filter still attached.
Had the oil filter not been present, this likely never would have happened.
Perhaps engineshould be shipped with oil filter off.

Why would anyone send an oil to a rebuilder?
What kind of engine would be $65,000?
I would think you are eating into turboprop territory at that price.

This is why amateurs should not work on aircraft, other than homebuilts.

A number of ‘fully dressed’ automotive crate engines come with the filter attached (at least according to the photos). I’d still assume no oil in the sump, as should have the pilot.

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I have never installed anything without adding oil to it (or checking 1st), I have over filled transmissions cause I didn’t know that that vendor sent them filled already… I learned to check before filling real quick I made a huge mess and brand new oil is VERY hard to mop up… lol

But incase I somehow, someway forgot to check the oil maybe cause I thought one of the other installers helping install the engine had checked it (just as an example), at startup when I noticed the “oil pressure gauge read ZERO” it would have been a red flag and my brain would have said to me, hey dum***** did anybody check the oil level??? NOT start checking wires and sensors or the “the oil monitoring system problem”… I bet these guys are the same ones that slap brake pads on and not pump up the brakes and wonder why they didn’t work when they backed into something cause they had no brakes…

I think it is a good idea actually to install the oil filter on an engine before shipping, even though it has no oil in the crankcase. The oil filter protects the oil filter adapter from getting damaged. Also would be a good idea to attach a sign or sticker to engine, big, bold lettering: “no oil in crankcase”. If I received an engine delivery , attached sign or not, I’d presume it has no oil in the crankcase. Similar to how if someone hands you a gun, experienced hunters & sportsmen will presume it is loaded with live-ammo and the safety is off.

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Wow, just checked price on a rebuilt Lycoming 6 cylinder, w/o core $77,000! Now I know why airboats use either SBC, Big Block Chevy, or 500CI Cadillac engines.

Wouldn’t a licensed aircraft engine rebuilder have to follow a procedure that I figure does not involve customer supplied break-in oil?


Most mowers and small engine equipment comes this way. You pretty much cannot pull the starter rope or open the gas cap without breaking a seal of sorts that says something like “Must add engine oil - failure to do so will result in engine damage and void warranty.”

Maybe the packaging on crate engines should be marked this way. I remember the mechanics that installed my Ford crate engine being surprised it came prefilled with oil and was ready to go.

The owner wanted a special break-in oil used.
When I had Walmart do an oil change in our Camry, I supplied Mobil1 full synthetic 0W-20 instead of their using their motor oil.
They checked the air filter and broke the filter box cover tabs. To keep the box sealed, I had to tie a rope around it.

Slightly more rules involved in performing an FAA-approved rebuild of an aero engine. Slightly…


Yes. More paperwork than a case of Charmin®

Being more ‘down to earth’ engine wise I’ll just mention that before starting any engine for the first time I install a mechanical gauge, then prime the oil pump with a drill when possible, otherwise with the plugs removed I spin the engine over until significant pressure is indicated. Even salvage yard engines seem to deserve that much concern to me.