My Yanmar 2gm20 has never been used, sat dry in a garage for 8yrs. Will it work?

tobyfaulkner

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I bought it recently, believe it's about 2005 model, but was never installed, never had fuel or oil put in it. Can anyone with a good knowledge of engines tell me if it's likely I will corrode in that time.
 
Why didn't you try turning it over before you bought it? If it's been stored in a reasonably dry place, I don't expect it will have been irrevocably damaged.
 
Turn it over - yes but remove the injectors first and put a little oil in each cylinder. If you turn it over dry (as it will be after being idle for so long) you will surely mark the bores and possibly damage an otherwise good engine.
 
Don't see why it wouldn't work.

Try to turn it over slowly clockwise with a spanner on the crankshaft nut. If it turns over at least you know it's not rusted solid!

Richard
Apart from taking the injector/s out and putting oil down the cylinder bores for 24 hours I would do the opposite of the above,
Try to turn the engine anti clockwise (the opposite of a compression stroke) and better still with the injector/s out.

I have a friend who told me to do this years ago, he buys e-army engines and places them in pallet racking and some of them have not been touched for 20 years, until they find a buyer
The fact it has been dried stored could be a problem. I would be inclined to fill the crankcase with diesel,(as a penetrating oil) leave for 24 hours, drain, refill with 10w40 which you could warm up in a pan on a stove and then pour in and rotate the engine anticlockwise so the rings don't stick (this is what you do if an engine has sized) and turn it over. I would probably try and do a compression test before I commit to installing in a boat.
 
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I wouldn't touch the injectors. One it's established it's not seized, turn it over and spray oil with an aerosol spray (ie 3 in one) into the inlet, not loads, there's a risk of locking the engine.
 
Re turning over; assuming it's not an "F" model, it will have a starting handle and de-compressers.
Good idea IMO to put some oil in the bores. Aerosol, or pump oil-can into air intake whilst slowly cranking.
 
Any reason not to fill it with oil and just turn it upside down for 10 seconds? That'll oil the bores. Darn sight simpler than messing with injectors, and I don't think aerosol oil (WD40?) will do any more than diesel fuel even if it gets into the pots which you'll never know.
It'll also get oil onto the camshaft, accessory drive geartrain and valve stems which are just as important.
Maybe a 2GM is a bit heavy for that.
 
you need oil in the bores for the very first strokes, as that is when the most damage would be done... turning it upside down is novel, but I don't think would work, as the oil would only go as far as below the rings

I agree, a bit of oil into injectors if poss... and then turn over by hand.

can't see why the engine would be anything other than fine.

i'd also take a good look at the perishables such as impellors, oil filter gaskets, etc before cranking her up if she's sat dry for that length of time... they should all be fine too, but no harm in checking.

PS... don't forget to treat her to a run in routine... early oil changes, restricted revs etc
 
Phoenix, I agree the foist few strokes are critical but squirting oil into the cylinder is pretty hit and miss unless you flood it and only gets oil above the rings, and leaves the rest of the engine unaffected (unoiled). Invert it and the oil would initially only be on the piston skirts, but saturating them which is where much of the wear may occur and the rings will distribute it up the bores in the first stroke or two. If I thought the engine needed a prelube I'd want oil everywhere, not just on the bores.

Actually I doubt any of this is really necessary if the engine was properly packaged and turns freely.
 
I would put oil in the sump and turn the block to ensure its coated the engine particularly the rings - I would then remove injectors and put a fair bit of oil into each pot, then with it decompressed turn slowly with ratchet spanner very slowly.
Would replace consumables including oil filter, impellors, fuel filter and check hoses for integrity. Not sure if the 2005 2GM had the new design crankcase gasket which was prone to fail on this engine fitted with original oem gasket but you might want to check with Yanmar or knowledgeable engineer who could advise whilst it is accessible change it if required.
 
How do engine manufacturers carry out initial lubrication?

Not unknown (if obsessive) for classic/veteran car owners to fit a hand pump lube in the system to send oil round before cranking.

While I don't think its needed, you could put a tee in the oil pressure sender tapping and pump in some lube with a suitable hand pump, then slowly hand cranking while the hand pump keeps the refitted oil switch light extinguished.

It'll be fine!

N
 
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