Starting 3YM30's after a 3 year rest

[gbraddon]

I have two Yanmar 3YM30's on my catamaran "Into The Mystic", unfortunately due to family problems, I have not started them in over 3 years. Does anybody have advice on procedures to prep and start these engines? Thanks, Glenn

[Seymore]

Take out each injector and spray fogging oil for 5 seconds into each cylinder. Turn the engine over manually for a few revolutions. Replace the injectors and start the engine.

These instructions are usually on the cans of fogging oil.

[sailormed]

change oil before your first start attempt and immediately after it has started and the oil is hot.

[Island Time O25]

If you have access covers to your diesel tank(s) check the condition of the diesel. If it was put away properly, i.e. topped up and with stabilizers, antibacterials, etc. added, it should be fine. If not, either empty the tanks by siphon or run diesel through some sort of filtration scheme before letting it reach the engine.

If the boat was put away with half empty tanks there would be some significant condensation water and/or bacterial muck in them.

[hasse_A]

I would also let the starter crank the engine with the stop handle engaged preventing the engine to start before you get oil pressure.

This will ensue that you get an oil film into the bearings before they get the load of the combustion. After a 3 year standstill there is probably no oil there anymore. I always do this when changing oil.

[flyingfin]

[QUOTE=Seymore;2542012]Take out each injector and spray fogging oil for 5 seconds into each cylinder. Turn the engine over manually for a few revolutions. Replace the injectors and start the engine.
/QUOTE]

Important - after shooting each cylinder with fogging oil, or Marvel Mystery Oil, lightly thread in the injector and let it sit OVERNIGHT. Then, drain your fuel tanks and replace with new diesel. The next day, remove the injectors, spray some more fogging oil and let sit for 15 minutes, do not replace injectors.
Then lightly bump the engine with starter. Repeat as many times as your patience allows. Goal is to ensure that you dont have a frozen piston ring that will immediately scar the cylinder wall should you attempt to fire it up and spin it up to 1,000 rpm!

[seabreez]

Originally Posted by gbraddon

I have two Yanmar 3YM30's on my catamaran "Into The Mystic", unfortunately due to family problems, I have not started them in over 3 years. Does anybody have advice on procedures to prep and start these engines? Thanks, Glenn

When shutting down a diesel engine the diesel fuel usually lubricates the cylinder. To start an engine that has been sitting for a while I would see if the engine turns over by hand first. Then introduce the starter momentarily. If the engine turns over... keep on cranking for 15 seconds or so. It should start. If not, crack an injector line and see if fuel is present or coming out. If fuel is not present. check for fuel at the fuel pump. If fuel is present at the fuel injector then try cranking over again. I had a Lister Diesel two cylinder on an industrial 4 inch gusher pump parked out behind my garage in the rain and snow and whatever. It was there for 12 years. This summer, to help flood victim we checked to see if the pump would turn over... it did! We installed a battery and turned it over to check for fuel... fuel was present! We turned it over for maybe 45 seconds and it started... to our SURPRISE! we let it warm up, added some more fuel and we went pumping.

[Boatguy30]

Have the water pumps been sitting with seawater in them this whole time. Would be wise to replace the impellers.

There is a manual stop on the injector pump. Hold that in while someone cranks the engine for 2 say 15 second bursts.

Forget the pulling injector business. If this was a 40 y/o crate engine maybe, but I bet 1/3 the sailboats out there have this kind of lapse at some point.

Also advisable to change fuel and oil and filters also

[Mike Banks]

Cranking the engine without a start could get water into the exhaust manifold from the heat exchanger to the mixing elbow. If you are going to do thuis sopinning the engine with stop button depressed--disconnect the hose from the mixing elbow.

[gbraddon]

Thanks to all for your advice on starting my Yanmar's. That's why I love this forum. GB