Starting 75 HP Yanmare Turbo Diesel after 18 years in storage

[birdsey]

Hello all,

I am considering purchasing a boat that has a 75 HP Yanmar diesel that was installed in a project boat, run in for an hour, then winterized for 18 years.

It is possible (and likely) that the engine was lubricated and turned periodically but no way to cofirm this.

It looks like new and would probably fire right up but I am interested in what precautions to take to ensure no damage is done in the short or long term from it sitting so long.

I know it would need a fresh, clean, fuel supply, new filters, and impeller.

I read one thread that suggested loosening the injectors, putting fuel or light lubricant in the cylinders, and turn it by hand a few revolutions without compression, then more with the starter, finaly re-tightening the injectors.

I saw another potential problem is that the springs in the engine can be damaged from sitting so long in one postition and should be replaced. THAT seems crazy.........but IS IT?

Please don't GUESS the right answer here. If you don't know, for sure, please don't comment. (I prefer that armchair quarterback just watch the thread and that people that actuallly do and know how to do "things" make the responses!)

[sailah]

I'd pull injectors and run bore scope to look at cylinders. Shoot some mystery oil in there, roll over by hand. Reinstall injectors. Pull valve cover, relash valves. Change oil, dump fresh oil on valve train. Reinstall valve cover.

Ensure fresh fuel supply, assume its bad
New oil and filters

Hit the starter and see what happens.

I'm not a pro but have been elbows deep in more than my fair share of diesels

[NCGunDude]

I can tell you that springs don't wear out from sitting compressed or uncompressed, only from repeated compression and decompression. Should apply to engine mounts the same as it does for ammunition magazines.

[Wotname]

Springs???
Maybe a typo for rings
or maybe meaning engine mounts
???

One thing I have done in the past is to spin the engine with injectors removed (and raw pump disconnected / /removed) for short periods to get oil circulating.

I don't think you can be certain about the long term health of the engine until you have completed the break in period.

[Wotname]

Dependant of the location (heat / humidity / cold etc), the hoses and belts might need replacing much sooner than later.

[a64pilot]

Originally Posted by sailah

I'd pull injectors and run bore scope to look at cylinders. Shoot some mystery oil in there, roll over by hand. Reinstall injectors. Pull valve cover, relash valves. Change oil, dump fresh oil on valve train. Reinstall valve cover.

This, I don’t understand the valve adjustment part, but it only takes a few minutes to check, and can’t hurt.
I’d also spin the motor with injectors out with the starter until there is oil pressure and oil flow observed in the valve train.
As long as the cylinders aren’t rusted, I’m certain it will be fine, properly put up motors can sit for a very long time, I know of a backwards turning Merlin that was found recently still preserved, that was in mint condition, and that was likely at least 60 yrs.

[sailah]

Originally Posted by a64pilot

This, I don’t understand the valve adjustment part, but it only takes a few minutes to check, and can’t hurt.
I’d also spin the motor with injectors out with the starter until there is oil pressure and oil flow observed in the valve train.
As long as the cylinders aren’t rusted, I’m certain it will be fine, properly put up motors can sit for a very long time, I know of a backwards turning Merlin that was found recently still preserved, that was in mint condition, and that was likely at least 60 yrs.

I just prefer to pour oil directly on valve train since you know it's bone dry after 18 years and valve caps/rockers are bare.

And since you have valve cover off and injectors removed, spinning over engine with socket on crank pulley is super easy. Gives you an indication of how tight engine is. Plus spinning by hand lets you visually see valve train working in all cylinders.

Adjusting valve lash is super easy at that point and just a good thing to check/adjust while you are in there.

Comes from my motorcycle days of any time valve cover is off, valves get checked, old habit. Probably overkill but why not right?

[jhulmer]

I happened across a 4jh3 HTE, new still in the crate, in a government auction two years ago. It was still factory pickled. I installed it in my boat while I am doing a complete refit.

I added oil, coolant and turned it over a few times with the starter while holding the stop button. Waited to see some oil pressure. Then hooked up fuel and she started after only a few seconds. Blew a lot of white smoke from the pickling and then ran like a sewing machine.

That is a 2001 engine that I installed 16 years later. No problems so far.

[seabreez]

Originally Posted by birdsey

Hello all,

I am considering purchasing a boat that has a 75 HP Yanmar diesel that was installed in a project boat, run in for an hour, then winterized for 18 years.

Please don't GUESS the right answer here. If you don't know, for sure, please don't comment. (I prefer that armchair quarterback just watch the thread and that people that actuallly do and know how to do "things" make the responses!)

I won't guess here... I do this kind of stuff often. The first thing you will do is check to see if the engine turns over. Not with the starter! I would try turning the crank pulley with the big nut or the flywheel. If this turns... it is good news. If it doesn't turn, the starter will not turn it over. If it turns by hand or wrench or socket and bar, then I would install a known good battery and check the connection ends to be sure there is good contact. When it is time to try the starter... just see if it clicks over and see if the engine turns over. If it turns over stop right there. Then check the oil, fill, I would pump the priming lever to see if fuel comes up, loosen a fuel line past the filter. Then I would try and start the engine. When the engine starts... then I would o the maintenance... filters, impeller, belts, electrical connections, fuel... if the tank is low I would simply add more and run the engine, the filter will pick up the dirt. I have started many diesel engines that where in the field at work! GM Detroits, Isuzus, Fords, Case, Listers, Cummings etc... and many of these were out in the elements for yearrrrs. If the engine does not turn over... sent me an email and I will walk you through the extended steps to start it... I could go on and on here... Good luck

[seabreez]

IMPORTANT, I forgot to add. If the engine has been stopped for a long period of time, I would check to see that the throttle control is free and returns to idle stop screw before starting. If it does not return and it starts it could run at high speed and blow up before you stop it. Lubricate before start up.

[Lepke]

I've done the first start on many mothballed diesels and other long sitting diesels. Some sitting more than 20 years. Truly mothballed, all openings are sealed and in the closed environment there is enough oil in bearings, etc., for a safe start. In sitting non-mothballed engines the issue is with the cylinders open to the environment, but diesels don't stick pistons as much as gas engines. I've never had a bad injector or fuel system part (I can remember). Most were large engines and didn't have a easy manual way for turning over without removing something. All turned with power or air. I flush the fuel with fresh except in engines from before the EPA when we had good diesel. Those you could just start up.
If they were put up as running engines, valve adjustments can wait until after the first start. Springs are ok. As seabreez says: linkage and governor check is important, but I don't think I ever had that problem. But have a way to stop a runaway handy. Never had that either.
I usually wait to change fluids and filters until after the first start. On big engines I have the oil tested since we're talking 50 to hundreds of gallons of oil.
For those on the Columbia River, this is what Tongue Point use to look like. Most ships were sold as scrap, Liberties went to cargo service, and many smaller ships were commercial fishing tenders and supply ships. Some smaller ships became Caribbean freighters.

[Cadence]

Originally Posted by Lepke

I've done the first start on many mothballed diesels and other long sitting diesels. Some sitting more than 20 years. Truly mothballed, all openings are sealed and in the closed environment there is enough oil in bearings, etc., for a safe start. In sitting non-mothballed engines the issue is with the cylinders open to the environment, but diesels don't stick pistons as much as gas engines. I've never had a bad injector or fuel system part (I can remember). Most were large engines and didn't have a easy manual way for turning over without removing something. All turned with power or air. I flush the fuel with fresh except in engines from before the EPA when we had good diesel. Those you could just start up.
If they were put up as running engines, valve adjustments can wait until after the first start. Springs are ok. As seabreez says: linkage and governor check is important, but I don't think I ever had that problem. But have a way to stop a runaway handy. Never had that either.
I usually wait to change fluids and filters until after the first start. On big engines I have the oil tested since we're talking 50 to hundreds of gallons of oil.
For those on the Columbia River, this is what Tongue Point use to look like. Most ships were sold as scrap, Liberties went to cargo service, and many smaller ships were commercial fishing tenders and supply ships. Some smaller ships became Caribbean freighters.

There was a mothballed fleet on the Hudson river also.
I would think sealing the air intake would be important. Humid air is not good.

[Mike Banks]

Pretty much what was said--but when you put lube oil into the cylinders, use a penetrating oil to ensure it gets into all of the ring grooves. I would like to see the engine spun on its starter without compression until the crankshaft is well lubricated without the compression and firing load.

The springs will be fine. This is a turbocharged engine, and it must not spin the turbo until the turbo has adequate oil in its spindle bearings--so just let it idle for a few minutes before advancing the throttle and opening the turbocharger to exhaust gas pressure. These things spin at very high revolutions, and lack of oil even for a second or two is fatal to their bearings.

[seabreez]

Originally Posted by Mike Banks

Pretty much what was said--but when you put lube oil into the cylinders, use a penetrating oil to ensure it gets into all of the ring grooves. I would like to see the engine spun on its starter without compression until the crankshaft is well lubricated without the compression and firing load.

The springs will be fine. This is a turbocharged engine, and it must not spin the turbo until the turbo has adequate oil in its spindle bearings--so just let it idle for a few minutes before advancing the throttle and opening the turbocharger to exhaust gas pressure. These things spin at very high revolutions, and lack of oil even for a second or two is fatal to their bearings.

I would not add any lube oil in the cylinders as some people do not know how much is adequate or too much, and this would greatly increase the compression and on some cases cause a lock up (too much oil to compress and the piston tries to compress this oil and locks up). And for you diesel guys, do not use starting fluids such as "ether". The rings will clean up the cylinders. May I add that after start up, let the engine run above idle to warm up. Watch the engine do not leave it alone. If oil, black oil spews out the exhaust pipe you probably have stuck rings. Do not panic! Here is what you do. Let the engine run just above idle. Then every time you have a chance floor the throttle for a second, then let it idle again, and then repeat this as many times as you wish. If it does not clear up,. keep doing this again and again and again. What this does is at every increase of throttle you increase the pressure inside the cylinder tremendously and this pressure pushed the piston rings outwards and tries to free the rings. This works for the top piston rings 1, 2, 3, and some 4 . And these are all the compression rings. For the oil rings, the piston has to warm up to operating temperature and the heat of dissimilar metal that expand at different temperature will free them up. On one case I had to do this increase of rpm's for 6 hours, one hour at a time. And all cleared up and now running life a top or (like sewing machine). This time spent for trying to free up rings is much better that an overhaul...

[Kiwi.]

Originally Posted by Mike Banks

This is a turbocharged engine, and it must not spin the turbo until the turbo has adequate oil in its spindle bearings--so just let it idle for a few minutes before advancing the throttle and opening the turbocharger to exhaust gas pressure. These things spin at very high revolutions, and lack of oil even for a second or two is fatal to their bearings.

Absolutely agree; I had a terrifying startup event with a turbocharged six cylinder (Yanmar 6LPA-STP2) that had the throttle stuck a little open. By the time we got it closed the turbo bearing seals had gone and the motor then started running on the oil feed to the turbo! Huge amounts of revs and smoke and no way of stopping it until the oil pressure dropped. Amazingly the motor survived (it is after all a Landcruiser based motor) but the turbo was toast.