Starting a diesel that sat 2 years

CapnBones · #1 (**permalink**) 05-09-2011

I just purchased a boat with a Yanmar 2GM engine and it has been sitting on the hard for 2-3 years now without being run. The engine will turn and has good compression and the oil looks pretty new in it. I am going this weekend to start cleaning the boat and want to get the engine fired. Aside from changing the filter/water separator adding fresh fuel and treatment and bleeding the line to make sure it is free of air. What other steps are recommended to making sure this engine is ready to fire and run this season. My experience is in gas motors which are cake, this diesel is a whole new beast for me. Any advice is appreciated, thanks in advance.

denby · #2 (**permalink**) 05-09-2011

Bones, what is the rest of the model #? Does the engine have glow plugs? If not then it might be a little ruff starting. Let me know. If the fuel is okay then that engine should start up.

CapnBones · #3 (**permalink**) 05-09-2011

I don't know the rest of the model number all I have to look at right now is the picture I have of the engine with the tag on the front. says 2GM also 13hp at 3400rpm. I am not sure if it has glow plugs, but I guess worst case I can hit it with some WD40. Now I have read some and I guess putting a biocide in should be a good idea, but I don't know how long that takes to work.

denby · #4 (**permalink**) 05-09-2011

Without glow plugs it will be ruff starting. You need to start it at almost full throttle, but keep a hand on the throttle to drop it down to an idle fast as soon as it fires. I wouldn't use WD40 or anything else to start it. Also don't crank it to long with the raw water valve open as you can have water backing into the cylinders. If I think of anything else I'll post it.

CalebD · #5 (**permalink**) 05-09-2011

Not to split hairs but it is probably a good idea to let a little water into the water pump for lubrication only. If you think it is going to be hard starting then open the raw water valve for one or two attempts to get it to turn over. Close it after that.
Some diesels have something called a compression valve that can be opened or closed. With the compression valve open (not compressed) you should be able to get the engine spinning faster. Once this happens if you shut the compression valve with engine spinning from starter motor it may just kick over.
I don't know if the 2GM has a compression valve.

denby · #6 (**permalink**) 05-09-2011

Caleb, my 2GM20F has compression valves but I don't think I would ever use them. They seam to be stuck.

bljones · #7 (**permalink**) 05-09-2011

The Yanmar GM series motors have decompression levers, which hold the valves open in each cylinder to allow the cylinders to warm up prior to attempting a full compression start. No glow plugs.

casey1999 · #8 (**permalink**) 05-10-2011

http://mysite.verizon.net/knellew/si...mar-manual.pdf

Manual is available above. I would drain oil and replace with new and new filter. Replace all fuel filters and also clean tank if it can be done easily, replace with new fuel. I did not do this after I bought my boat and engine died several times, once when coming into dock. If sediments at bottom of tank they will get disturbed at sea and clog filters.

Check the manual. They reccomend opening the decompression levers and turning over engine without starting (pull stop cable while running the electric starter) to get lube oil circulated if engine has sat for a long time.

Good luck

arf145 · #9 (**permalink**) 05-10-2011

Biocide is more to keep stuff from growing at the juncture between fuel and water, but it won't help what's already there.

I would replace the raw water impeller, since it has been bent in the same position for a while. I second changing the oil and filter, even though that looks good. A few cranks with the stop knob pulled out to circulate oil sounds good.

After you replace the fuel filters and bleed (don't crank down that bleed screw on the secondary filter too hard or you'll strip out the aluminum housing), I would not be surprised if it started right up. The full throttle just to start trick that denby suggests works for my 2GM20F, but I only need it in really cold weather.

And as others have mentioned, don't crank for too long with the raw water seacock opened to the engine (20 or 30 seconds total). Flooding the engine with water would be a lousy start.

CapnBones · #10 (**permalink**) 05-11-2011

It is out of the water now I don't want to run it long, just make sure it does, but I have seen that about keeping the raw water shut off to not flood the cylinders if cranking for a long period, I will make sure to remember that when it gets in the water. I was going to try and siphon from the bottom of the tank to see how bad the fuel looks and remove any sediment that has settled.

Thanks for all the good advice, and cross your fingers for me.