Preventing Corrosion in a Laid up Engine
Discussion
I'm working on a long term project on a Mk2 Polo Coupe with a Polo G40 engine (a project thread will follow soon). The engine hasn't been run since October and isn't likely to be run for at least a few years. One thing I've been wondering recently is if it's in danger of corrosion inside the engine. Whilst it's garaged, I'm concerned this may be an issue in areas such as the cylinder walls.
It has been suggested to me in the past that I could pop a few drops of oil inside the spark plug holes and turn the engine by the crankshaft bolt, which I've done. However, as the pistons are dished, I'm guessing a lot, if not all of the oil will just sit inside the piston dishes. I've noticed on a lot of American car forums that people use oil fogging sprays, but I don't see much mention of these in the UK and I'm wondering why.
Does anyone have experience with laying up an engine long term like this and what would you recommend? I did an oil change on the car before laying the engine up. Will this be sufficient to protect the drier areas of the engine? Am I just worrying about nothing, or are there preventative actions I should be taking? If there's a product I should be using, can anyone recommend one as well as the means to apply it?
It has been suggested to me in the past that I could pop a few drops of oil inside the spark plug holes and turn the engine by the crankshaft bolt, which I've done. However, as the pistons are dished, I'm guessing a lot, if not all of the oil will just sit inside the piston dishes. I've noticed on a lot of American car forums that people use oil fogging sprays, but I don't see much mention of these in the UK and I'm wondering why.
Does anyone have experience with laying up an engine long term like this and what would you recommend? I did an oil change on the car before laying the engine up. Will this be sufficient to protect the drier areas of the engine? Am I just worrying about nothing, or are there preventative actions I should be taking? If there's a product I should be using, can anyone recommend one as well as the means to apply it?
Firstly, it'll probably be fine. I had an engine in the garage for a few years before I stripped it and it was fine inside.
Otherwise, squirt WD 40 into the plug holes every so often. If you're really worried, you could take the head off (if you're going to rebuild it anyway?) and oil it directly.
Otherwise, squirt WD 40 into the plug holes every so often. If you're really worried, you could take the head off (if you're going to rebuild it anyway?) and oil it directly.
Just to add that masking paper and pen fades, so if you have labeled everything like this, write it with pencil instead.
Agree with laying up of boat engines.
Personally would not take the head off until the time comes as everything is in the correct place now. (unless there is a chance that when you take the head off you find a terminal problem and you need to find another engine that fits.)
Agree with laying up of boat engines.
Personally would not take the head off until the time comes as everything is in the correct place now. (unless there is a chance that when you take the head off you find a terminal problem and you need to find another engine that fits.)
Oily engine internals don't seem to suffer much, once it's got an oil film on it and it's sealed the oil stays there. Don't forget the cam lobes if it is left for a long time, i've seen those with rust on them sometimes as by nature they don't have much there to start with.
What I have also seen is the waterways eroded, this is caused by no anti-freeze or old anti-freeze which turns acidic after a certain time. If the block has a drain plug use it, you'll generally find that by just undoing a rad hose etc to drain down often leaves a fair bit in the engine so either put some fresh blue in which will do a few years or red (OAT) which goes for much longer.
What I have also seen is the waterways eroded, this is caused by no anti-freeze or old anti-freeze which turns acidic after a certain time. If the block has a drain plug use it, you'll generally find that by just undoing a rad hose etc to drain down often leaves a fair bit in the engine so either put some fresh blue in which will do a few years or red (OAT) which goes for much longer.
Thanks for the tips chaps 
I did have a look on winterising boat engines and there was a fair bit of information about people using fogging oils, but I also saw mentions that they should be avoided on fuel injection engines. Whether this has any merit or not is another thing...
Does anyone have any experience with fogging oils and can you recommend any in particular?
The engine itself only has 10k on it, so isn't going to be rebuilt. I feel reasonably comfortable that it should be fine in the environment its being stored in, but as it is a garage, it can get cold in the winter months I'd like to err on the side of caution.
I did have a look on winterising boat engines and there was a fair bit of information about people using fogging oils, but I also saw mentions that they should be avoided on fuel injection engines. Whether this has any merit or not is another thing...Does anyone have any experience with fogging oils and can you recommend any in particular?
The engine itself only has 10k on it, so isn't going to be rebuilt. I feel reasonably comfortable that it should be fine in the environment its being stored in, but as it is a garage, it can get cold in the winter months I'd like to err on the side of caution.
I drained the fuel a few months ago; that was 12 litres of "free" petrol for my daily driver
As for plugging the ports, I've just popped a small breather filter on the throttle body and I was going to pop something on the exhaust manifold once I've removed the engine from the bay. That way I'm not trapping moisture in there if it does form. How does that sound?
In the meantime, I've turned the engine a couple of times on the crank bolt. I'll just pop into the garage every weekend and do that.
Good point about the brake discs. The discs have a few rust spots on them, but that's not bad considering it was out in the rain all day a few weeks ago whilst I was sorting out the garage. If they're doing okay, I'm guessing that the cylinder internals with a bit of oil residue will be fine.
I actually just had another thought... I have a souvenir from when I melted a piston about 10 years ago. That's been kept in all kinds of environments and hasn't corroded at all. I'm guessing the tiny covering of oil does a lot to protect it!
As for plugging the ports, I've just popped a small breather filter on the throttle body and I was going to pop something on the exhaust manifold once I've removed the engine from the bay. That way I'm not trapping moisture in there if it does form. How does that sound?
In the meantime, I've turned the engine a couple of times on the crank bolt. I'll just pop into the garage every weekend and do that.
Good point about the brake discs. The discs have a few rust spots on them, but that's not bad considering it was out in the rain all day a few weeks ago whilst I was sorting out the garage. If they're doing okay, I'm guessing that the cylinder internals with a bit of oil residue will be fine.
I actually just had another thought... I have a souvenir from when I melted a piston about 10 years ago. That's been kept in all kinds of environments and hasn't corroded at all. I'm guessing the tiny covering of oil does a lot to protect it!
You need to be very careful spraying anything into the plug holes, as by their recessed nature hold dirt that can get washed in with a spray- so at least use a pipe on the spray head to get down to the combustion chamber. Dont make the mistake I did once of using a silicone lube spray- lambda sensors die with a whiff of the stuff.
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