Okay, another posting about long term engine storage. I have an experimental Lycoming O-235 in an EAB airplane that I can't run with preservative oil before putting into storage. It will be hangared in a high humidity region for a couple years. Camshaft corrosion is the concern. I plan to remove the rockers, then rotate the crank to push all the tappets away from the cam. This should make it easy for oil to completely coat the cam lobes and tappet faces. I plan to fill the crankcase with oil, but first turn the breather elbow up and install a clear tubing vertically onto the elbow. When the crankcase is full, the oil level should show in the clear tubing. With the rockers removed, all the valves will be closed, thus keeping moisture out of the cylinders. I am trying to decide if it is better to drain the oil back to normal level, or keep the crankcase full. If I drain the oil, I can repeat the fill procedure several times a year to recoat the surfaces. Anybody have an opinion of what is best, or see any potential problems with this plan?
Long Term Engine Preservation
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Dan Thomas
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No need for that much oil. Just plug things and store the engine inverted.
Engine is going to stay on the fuselage while in storage. This option is not practical
Stewartb
Final Approach
When Lycoming fills engines with oil to ship everything (accessories, mags, intake tubes, exhaust, carb) is removed and blocking plates installed. If you aren’t prepared to do that? Don’t fill it.
Why not follow Lycoming instructions for preservation? https://www.lycoming.com/sites/default/files/Engine Preservation for Active and Stored Aircraft.pdf
Since you can’t run it just remove the plugs and do a pre-start pre-oil routine. Crank it to achieve oil pressure. I’d use a marine engine fogging oil for the cylinders. LPS-3 or CorrosionX Marine would be a good choice, too.
Why not follow Lycoming instructions for preservation? https://www.lycoming.com/sites/default/files/Engine Preservation for Active and Stored Aircraft.pdf
Since you can’t run it just remove the plugs and do a pre-start pre-oil routine. Crank it to achieve oil pressure. I’d use a marine engine fogging oil for the cylinders. LPS-3 or CorrosionX Marine would be a good choice, too.
I can't run the engine up to 180 oil temp, so Lycoming's instructions aren't applicable.
I am willing to do this if that's what it takes to save the engine from corrosion. The difference is that factory shipped engines will have the rockers installed. This will keep some of the intake and exhaust valves open, allowing oil in the cylinders to drain into the intake and exhaust tubes. With rockers removed, all valves will be closed so no oil should get into the exhaust and intake. If I fill the engine just long enough to coat the cam & then immediately drain it, I don't think oil will have enough time to get through the ring gaps into the cylinders. So its only the mags that are left. I can remove and block them if a few minutes of the crankcase filled with oil will hurt them.
I have an electric pre-oiler system that I use on all my automotive and truck engines prior to starting after storage. I can use it on the lycoming, but it won't do anything for the cam lobes. I don't know if starter cranking rpm's are going to be enough splash to create the oil misting for the cam. I sure would like to know if there is any information that shows if cranking with no-start is sufficient to spray the cam. I think with the tappets pushed away from the cam lobes, it will only take a few seconds to coat the cam and tappets when submerged in oil (not cranking the engine). I think I only need to have oil in the engine for a few moments. Without the cam contacting the tappets, shouldn't this reduce the galvanic corrosion process?
Stewartb
Final Approach
Pre-oil using the starter with plugs removed. Works great. If you can visit the plane a couple of times a year? Add an engine dehydrator. If you can keep the engine case at under 10% humidity it won’t rust.
Galvanic corrosion occurs with dissimilar metals in the presence of an electrolyte. Preservative oils are made to coat the metal and stay there. Subsequently it protects from rust. In my 29 years of winter storage I’d say it works as advertised.
PS- when Lycoming ships engines with sump, induction, and cylinders filled with oil, they label the crates that the engine preservation is good for 60 days. Probably a conservative disclaimer but…..
Galvanic corrosion occurs with dissimilar metals in the presence of an electrolyte. Preservative oils are made to coat the metal and stay there. Subsequently it protects from rust. In my 29 years of winter storage I’d say it works as advertised.
PS- when Lycoming ships engines with sump, induction, and cylinders filled with oil, they label the crates that the engine preservation is good for 60 days. Probably a conservative disclaimer but…..
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Dan Thomas
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The cam and tappets are both steel and there is no galvanic action between them. There would be more action between the cam and its aluminum bearing bores in the case, but that isn't a problem. The cams and tappets are exposed to the air inside the engine, and any moisture in that air can lead to corrosion. That's what ground-running does: adds terrific amounts of water to the case. Atmospheric moisture is negligible in comparison. When was the engine last run, and under what conditions? You might be overthinking the whole thing.
Might be able to fog the case via the dipstick tube, letting the air out through the breather. Once fog is coming out the breather, you've got everything inside wet.
I might be overthinking it, but not thinking it through can be much more costly. I have a Lycoming O-540 that had 100 hrs since factory reman. It had a prop strike, so we decided to tear it down for inspection and not reassemble until the project was ready for the engine. Everything looked brand new internally. I sealed each connecting rod inside ziploc bags and stored in a climate controlled shop. 2 years later, the connecting rods were heavily rusted inside the bags. I'm not taking chances on something that I can't see inside the engine and is known to corrode. Maybe fogging will do it, but I am still going to release the rocker arms because I don't see how fogging oil will be able to get between a cam lobe and a tappet that is pushing open a valve.
455 Bravo Uniform
Final Approach
Pull each spark plug and fog cylinders with oil (compressor and a wand with an eductor in a container of oil). Do the same with the crankcase thru whatever holes you have access to.
Next concern is if you have a constant speed prop. Not sure how to preserve that (intervals that is). Remove prop and take it in the house. Nice decor.
Next concern is if you have a constant speed prop. Not sure how to preserve that (intervals that is). Remove prop and take it in the house. Nice decor.
OP
Are you familiar with desiccant ?
Not only does it absorb moisture but in doing so the color changes from blue to pink as an indicator also. You can boil the moisture out too. Available in dummy spark plugs , bags and crystals. You could bag engine and install plugs and pack bags in. I’m a fan of engine dryers ( desiccant also) that you could hook up to the bag.
Are you familiar with desiccant ?
Not only does it absorb moisture but in doing so the color changes from blue to pink as an indicator also. You can boil the moisture out too. Available in dummy spark plugs , bags and crystals. You could bag engine and install plugs and pack bags in. I’m a fan of engine dryers ( desiccant also) that you could hook up to the bag.
Dan Thomas
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Yup. Moreover, if the engine oil wasn't washed off, and that oil had water contamination from a short flight or ground run, that water was sealed inside the bag with the con rod. Of course it will rust.
We regularly get pilots asking about that coffee-colored goop on the hangar floor under an airplane's breather tube, especially in colder weather. That goop is that color because it's an oil-water emulsion, created by water from blowby gases and the engine oil and all the turbulence and mixing going on inside the case. In colder weather more of the water vapor condenses inside the case instead of being blown out the breather with the other gases. Short flights or ground runs make a lot of that stuff, and it turns to acids and eats the engine.
donjohnston
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Curious, why cant you run the engine? Regardless, give Lycoming tech support a call for a process. I've used a modified preservation procedure they supplied in years past. I dont recall the details but it did require additional follow up applications.
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Light and Sporty Guy
Put it in a freezer. Lower temperature, slower corrosion.
It may be worthwhile to research some Military Technical Orders ( TO’s ).
I’ve often seen engines packed in “ drums” for long term storage.
The Impulse Coupling Spring could be the “ Canary in the coal mine”.
I’ve often seen engines packed in “ drums” for long term storage.
The Impulse Coupling Spring could be the “ Canary in the coal mine”.
bluerooster
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shorty
Friend of mine had his Jake R755 stored in a vat of oil. completely submerged.
Back in the day in my neighborhood a fellow had a 426 hemi disassembled submerged in motor oil in a open tub. He showed it to us, well I think he did? All I ever saw was a connecting rod and piston.
Wonder what ever happened to it?
This is what I did today. Removed all rocker arms, sprayed fogging oil in cylinders, rotated crankshaft 2 revolutions, removed intake tubes, installed rubber hose on breather with open end raised above the engine block, drained all engine oil. I proceeded to add Phillips 66 Aviation Anti-Rust oil through the fill tube until oil in the breather hose was visibly higher than the engine block (6 US gallons). I let it sit for 30 minutes, and then I drained 4.5 gallons oil (leaving 6 quarts in the engine). I finished it off by capping the breather tube. I sprayed the rocker arms with fogging oil and put them in sealed containers.
I feel good that this will protect the engine from corrosion for the long term storage in a humid environment. The 4.5 gallons of oil were drained into a clean, sealed container so I can refill and drain every 6 months providing renewed oil coverage of internal components. With all valves closed, no moisture should be able to enter cylinders. Without pressure contact between the vulnerable cam lobs and lifters, I am confident all surfaces are oil coated.
I tried experimenting with the suggested easier method of spraying fogging oil into crankcase, but I was not satisfied with the results. Without being able to run engine to follow Lycoming's service instructions, I feel this is the best method for my situation.
I feel good that this will protect the engine from corrosion for the long term storage in a humid environment. The 4.5 gallons of oil were drained into a clean, sealed container so I can refill and drain every 6 months providing renewed oil coverage of internal components. With all valves closed, no moisture should be able to enter cylinders. Without pressure contact between the vulnerable cam lobs and lifters, I am confident all surfaces are oil coated.
I tried experimenting with the suggested easier method of spraying fogging oil into crankcase, but I was not satisfied with the results. Without being able to run engine to follow Lycoming's service instructions, I feel this is the best method for my situation.