Yanmar NON Use

[CampDavid]

Looking at buying a Beneteau with a 4JH4TE. Long story. Been on the hard in Grenada for 7 plus years. Was launched two years ago with the engine and gen set running from aux fuel tanks.

The owner is sick and hard to communicate with. I believe he laid it up with the intent to back in 6 to 9 months. Prior to the lay up he took very good care of all systems. To the point he installed a complete new engine prior to sailing to the Grenadines in 2008.

The engine has 600 hrs.

What’s the risk of seized rings and or internal corrosion from a lengthly lack of use?

Can you find out much from running the engine at the dock or a sea trial?

Suggestions

Camp David

[roverhi]

You really don't know till you try and start the engine. My Yanmar has gone six months or even longer between runnings without a problem. Have had car engines that have sat for 10 years and still started with a little coaxing with starter fluid. Then have seen engines frozen up after less than a month when they got salt water in them. Diesel lasts a long time but if we're talking 7 years would pump it out and put in new. If it's got compression releases would pop them, close the sea water inlet, and turn it over while squirting light oil in the intake till the oill pressure built up. Then close compression releases, open the water inlet and see if it will start. If it will turn over would be willing to bet it will start.

[a64pilot]

I’d remove the injectors and put in a couple of ounces of Marvel Mystery oil or transmission fluid in each cylinder and then next day turn it over with rags on the injector holes to catch the oil spray, turn it over for 30sec or so to make sure oil is getting everywhere and reinstall injectors and start up.
Might want to wrap a rag around each fuel line as some will spurt out unless fuel shut off is engaged.

The oil is likely unnecessary but goes into the can help, can’t hurt and is easy to do category, turning it over without compression is the same, may help, can’t hurt.

Do NOT replace the injectors without spinning the engine and letting the oil blow out, or you could hydrolock it and hurt something

My boat motor was 27 yrs old and had 500 hours on it when I bought it, think just maybe there were long stretches when it wasn’t run? Probably more than one.
Since then I have put another 800 or so on it and it seems fine, burns no oil and cranks easily etc.

[Cheechako]

Try to turn it over by hand, it might be fine. But sure, why not open it up and put some lube in there for a bit first.

[Island Time O25]

I had an ancient QM Yanmar which sat for at least 6 years unused. After some starter work (original starter), oil change, a new battery and a new high pressure oil line it purred like a kitten.

[CampDavid]

Thanks to all