Corrosion comment; Panasonic???

[boscoe99]

I know you are a turbine guy but I suspect that you must also have some aircraft piston engine experience. Below is a link to a video from RAM aircraft that addresses corrosion in infrequently used aircraft piston engines. Do you feel that aircraft engines are more susceptible to corrosion than outboard motors? If so, is the type of metals used? I am surprised that outboard motors have as little corrosion related failures as they do given the environment in which they operate, and the amount of time they sit idle. Particularly the cam shafts and valve buckets.

https://www.avweb.com/videos/Engine-...-228567-1.html

[panasonic]

Short answer is...I don't know.

I watched the video and there is some bad corrosion shown for sure. I don't have hardly any piston time, but I have a few friends with small piston poppers that I will fool around with at times.

Here is what I think.

The small aircraft engine designs are old but dependable...a proven design. They have not changed much in last 60 odd years, and to change and/or redesign a component (material) is a huge undertaking requiring years of testing and large liabilities involved. I knew a guy that worked with me that went to a company that was trying to develop a "new" small aircraft certified engine using an existing automotive block. They worked at that for more than 10 years and the company never did get that engine certified...went out of business. That piston market is very,very slow to change for many reasons.

I would venture to say that the material's used in a modern day 4 stroke outboard are better then all the old aircraft engines have in them...corrosion resistance,durablitly, ect So add that to the infrequent use cycle of outboards and small aircraft and you have a recipe for rust. Seems like the aircraft engines get the worst of it though, just like you said.

I don't think aircraft engine oils have many additives in them either...pretty much plain old oil??

Time between overhaul on typical aircraft engine is 2000 to 2500 hours, not much really.

Saying all that my buddies Cessna is pretty much done now for the winter, so it will go into the hanger for 6 months. He will add some product to the oil, run the engine for so long and then spray a bunch of oil in the cylinder's, drain carb. Turn over the engine by hand a few times this winter. That's all he does with it. Next spring he will change oil, filter and go.