Just trying to get the feel of a normal life of engine operation of Lycoming O-320 E2D.
Engine was overhauled in 1981 0-SMOH with not much else given but some simple logbook entries. I do not know if cylinders were new or overhauled at that time.
Engine now has 1,550 hours on it SMOH.
Cylinder #3 was replaced twice.
The first time it was replaced with a used but serviceable cylinder at 900 SMOH, and then at 1300 hours SMOH that used cylinder had low compression and was replaced again with a overhauled unit.
Cylinder #2 was repaired once due to a broken ring. (honed and new rings) at 1,300 SMOH
Cylinder #1 was just replaced due to low compression with overhauled unit. Crack found by the exhaust valve. exhaust valve guide worn.
Cylinder #4 (according to logbooks) appears to be original.
at that same time 1300 hours SMOH (year 2014) the cam and lifters were examined and found to be in mirror like condition. Two senior mechanics looked it over and said "just fix the cylinders and go fly it".
The reason I am asking is that I am aware of a few O-320's on the field that made 2,000 hours without any cylinders replaced. Perhaps the owners are not providing correct information?
I am trying to get a 'feel' for what is normal and what is not on these engines. And considering how long ago mine was originally overhauled (1981) perhaps I am lucky to even go this long before needing a complete overhaul?
If the oil pressure is good, compression good and it is not making metal in the filter, i would fly it. I have seen a lot of 0-320’s way over official tbo hours that when torn down look great. The key is to fly it and not let it sit around. Flight school engines rarely have serious issues. Engines flown 20hrs per year have a tendency to have rust in the bores and spall lifters from lack of use. I just finished my engine overhaul due to lack of use. Plane sat for years with very little flying. I bought it and started flying 70hrs per year. The engine lasted 100hrs after being put “back in regular” service before the lifters were trash. Cost me $20k for the overhaul, but i did a lot of things that was expensive to get the 190+hp out of it.
Last edited: May 1, 2019I've got an O-320 in '67 Citabria. 2,165 hrs and never been touched. Still has above 70 on all cylinders and oil pressure above 60. Recently started using oil, maybe from front main seal.
Keep in mind that your 1550 hr engine was overhauled 38 years ago! That's a long time, (3X recommended calendar overhaul), and including a checkered history of cylinder replacement/repair. If you want a reliable engine you can count on, and can afford it, I would go for a quality overhaul. But once that's done it needs to be flown, regularly and often. Lycoming SB1009 allows for a 200 hr tbo extension for engines that meet a minimum use schedule. There is a reason for this, THESE ENGINES NEED TO BE FLOWN. If you are a 50 hr/year flyer then don't bother, just keep replacing cylinders or whatever else needs to be done on condition.
Last edited: May 1, 2019Hey Guys above, How often is good to keep your engine good, as referenced above? I fly about twice a month or maybe every two weeks or so. Is that good??
