Thu Jan 25, 2018 5:22 pm
#1586296
Lycoming https://www.lycoming.com/sites/default/ ... rcraft.pdf
I suspect the difference is speed - a starter is much faster than slowing pulling a prop through, so can still do the splash lubrication.
Service Letter No. L180B wrote:Pulling engines through by hand when the aircraft is not run or flown for a week or so is not recommended. Pulling the engine through by hand prior to start or to minimize rust and corrosion does more harm than good. The cylinder walls, piston, rings, cam and cam follower only receive splash and vapor lubrication. When the prop is pulled through by hand, the rings wipe oil from cylinder walls. The cam load created by the valve train wipes oil off the cam and followers. After two or three times of pulling the engine through by hand without engine starts, the cylinders, cam and followers are left without a proper oil film.(my bold)
Starting engines without proper lubrication can cause scuffing and scoring of parts resulting in excessive wear.
I suspect the difference is speed - a starter is much faster than slowing pulling a prop through, so can still do the splash lubrication.
Last edited by riverrock on Thu Jan 25, 2018 5:27 pm, edited 1 time in total.