Yanmar 2gm2f no start after fueling

alechich · #1 12-14-2012

Hi All: have had my repowered (1991) yanmar in pearson 30 for one season and always ran great. then after topping off tank for the winter it started and after about 5 seconds petered out with a lot of shaking and stopped. couldn't restart, though never applied more throttle as said elsewhere on this forum, since never needed to before. manual says to check air intake and fuel (obviously). only checked and cleaned sea strainer first (it wasn't too bad). could an air intake or vent be related to filling the tank? the final level was definitely below the neck. i think this is original tank, probably from an original universal? i'll check the fuel filter(s) next but would like to know of people's opinions also.
Alex

jsaronson · #2 12-14-2012

Long shot: Fuel tank vent is clogged, Tank cap was loose before you refueled. Now its creating a vacumn.

jrd22 · #3 12-14-2012

1. clogged filter from stirring up crud while fueling
2. water in fuel/filters
3. pick up screen in tank clogged

SlowButSteady · #4 12-14-2012

I can turn off the fuel valve (at the tank) in my boat and my 2GM20 will run for a few minutes, so I doubt that it's a clog anywhere very far upstream of the high pressure pump. Make sure the pick-up pump hasn't lost its prime for some reason (i.e., bleed the system). If the pick-up pump seems to be getting fuel, then the problem must be in the high pressure pump or the injectors.

alechich · #5 12-14-2012

Thanks for great responses so far. for first one, Fuel tank vent is clogged, Tank cap was loose before you refueled. Now its creating a vacuum; the cap was definitely not loose. but how does vent get clogged, from fuel? (i don't know where it is in any case, looked in filler neck tube but can't see anything). for other ones; i'm not sure where the pick up screen or pump is but will look for it (them). i also thought it may be crud stirred up while filling, so guess i really need to find the pickup pump/screen. to bleed i understand there's a screw or two. do i just open it and listen for air running out or just leave open for a while? sorry, i'm not a mechanic, just starting to learn about the engine.

SlowButSteady · #6 12-14-2012

Get a manual for you engine. Seloc manuals are fine for most routine stuff (WestMarine should have one for a 2gm20), and there are some PDFs of actual Yanmar manuals online (Google is your friend). Bleeding the system isn't hard, but it isn't how you describe either.

alechich · #7 12-14-2012

Thanks Steady, i did download a yanmar manual for the engine but it doesn't go into mechanical detail. i'll be able to find the engine fuel filter/pump using it but don't know about the tank pump/screen etc. will get back in there and look real closely for it. i'm intrigued by the tank air vent issue though since the manual also mentioned it, though it's not part of the yanmar system and of course not shown. any idea where i should start looking for it, and if i find it how to figure out if it's clogged?
Thanks again.

SlowButSteady · #8 12-14-2012

Quote:

Originally Posted by alechich

Thanks Steady, i did download a yanmar manual for the engine but it doesn't go into mechanical detail. i'll be able to find the engine fuel filter/pump using it but don't know about the tank pump/screen etc. will get back in there and look real closely for it. i'm intrigued by the tank air vent issue though since the manual also mentioned it, though it's not part of the yanmar system and of course not shown. any idea where i should start looking for it, and if i find it how to figure out if it's clogged?
Thanks again.

If it only ran for a few seconds the problem isn't a clogged vent. Again, I can turn off the fuel at the tank, or start the engine with the valve closed, and my 2gm20 will run for several minutes before dying.

jsaronson · #9 12-14-2012

the pickup is in the tank. you need to remove the line that goes through the top of the tank.

fryewe · #10 12-14-2012

As SbS sez --- your engine should run for several minutes on the fuel within the fuel distribution system of the engine with the fuel supply from the tank shut.

Ergo the failure of your engine to run for more than five seconds after fueling is unrelated to the fact that you just fueled.

And it's likely you either lost prime in the fuel distribution piping or you have a fuel injection pump problem.

Good luck.