A hanger neighbor asked me how many hours should be on an engine before she can begin running it LOP. I would think at least 50 to 100 hours, but I want to make sure Im providing her accurate information. So how many hours should be on an overhauled engine before operating it LOP?
Van's Air Force
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New engine and LOP
- Thread starter togaflyer
- Start date
https://www.lycoming.com/content/hard-facts-about-engine-break
This should answer your question.
Tom.
This should answer your question.
Tom.
PilotjohnS
Well Known Member
Prez oil
Funny it says you can leave the preservation oil in the engine for 25 hours, I always thought in prep for first flight it should be drained and replace with the mineral break in oil. Comments?
I was flying a spam can to Vegas with a new engine. The FBO said to run it hard to break in; never a problem for me in a rental. About 45 min out, climbing over the pass, the rpm increased about 150 RPM ( fixed pitch prop) and the temps all came down. It seems the conclusion of the break in was quite sudden.
Funny it says you can leave the preservation oil in the engine for 25 hours, I always thought in prep for first flight it should be drained and replace with the mineral break in oil. Comments?
I was flying a spam can to Vegas with a new engine. The FBO said to run it hard to break in; never a problem for me in a rental. About 45 min out, climbing over the pass, the rpm increased about 150 RPM ( fixed pitch prop) and the temps all came down. It seems the conclusion of the break in was quite sudden.
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Ya a lot of their other manuals and service letters say to drain it. I personally drained it but was surprised at how little there actually was in the engine.
When I was doing break in I never saw any of the CHT changes that others mention. Oil consumption was always around 1-2 qts per 25 hours too. I suspect the break in was pretty much done on the test stand.
scsmith
Well Known Member
I had the same experience. I think it was already broken in from the run-in on the test stand by the engine builder. I did do 5 hrs of hard running with mineral oil, then changed the oil and started LOP ops.
Interesting but...
I only presume to run it rich enough to keep the temps in control during break-in???
Interesting read but there's no mention of mixture adjustments during or after break-in.
I only presume to run it rich enough to keep the temps in control during break-in???
That's what most people do (as did I). Erring on the side of too rich seems to be typical early on for most. Don't forget to read the full service instruction from Lycoming #1427C. If you pay good attention to your baffles from the start CHTs will be in check.
Luckily you are so close to sea level that your takeoff full rich will show you your target EGT.
My IO-360 M1B from Lycoming has the nitride lined cylinder (blue paint on the fins). Mike Busch was saying the nitride lined cylinders breaks in the fastest, in a 1 or 2 hours. My engine from Lycoming has about 2 hours of running on the test stand. Chrome line cylinder took the longest to break in.
