I need help bleeding the fuel line on a Yanmar 2GM motor

[bobsellie]

Hello,
Well my water seperator had crud in the bottom of it, so I drained it. Then I started the motor and it ran great. I shut it off, and later I started it and it ran great again. Shut it off, and later started it again. It ran then died. I didn't refill the fuel sediment bowl (water seperator) so I'm thinking it "ran out of fuel." I cranked it until the bowl was full. I looked up "bleeding the fuel line on a small yanmar diesel" on youtube and it went through it pretty well. But I still can't get it started. There is something between the fuel filter and the water seperator. It has a lever on it, that a mechanic told me it's some type of an override pump. Question: Can that be used to bleed the system instead of turning the engine over with the key? Next. I unscrewed the 2 bleed screws on top of the fuel filter, but no fuel ever came out. The fuel filter was replaced last year. Question: Could it be there is water in there and should I drain and clean it? I undid one of the bleed lines from the injector, but no fuel came out of there either. Any tips?? Does this sound like it could be a fuel pump issue? I just bought the boat, but the motor has run like a champ, up until I drained the water seperator. That's what leads me to an air in the line problem. I've never owned a diesel motor, nor have I ever bleed the fuel lines. It's just hard for me to pay a mechanic $150 bucks to do it, because I know I'd slap myself and say, "I could have done that."
I'd appreciate the help.
Thanks,
Bob Sellie
"Sköl"

 

[Ed Schenck]

First question Bob, how many minutes total did the motor run after cleaning out the crud? More than two or three and you would have to believe the fuel pump, the thing with the lever, is working correctly.

Some have had success with bleeding by using the lever on the fuel pump to build pressure as you open the bleed screws. It depends upon where the pump is left in relation to the cam that drives it. I never could do it with that lever.

 

[Paul F]

Yes, take the secondary fuel filter apart and see if it is plugged up. If you had crud in the first filter you likely have crud in the second one too. Take a look and make sure. Then leave the cap off the secondary filter and see if the engine/fuel pump will pump fuel to the cap. If it does, fill the secondary filter and go on with bleeding the engine. If you can not get fuel to the secondary filter the fuel pump is very suspect. I replaced mine with an electric one and am very happy with it. Just turn it on and fuel line bleeding is a breeze. Here is a site with a service manual for your engine. Read up on how to bleed a fuel line.
http://www.motoren.ath.cx/menus/yanmar.html

 

[Ed A]

the above ideas are good, but, you can not bleed the system unless the engine is turning. It sounds like you ran it out of fuel. then started it and air is in the system. so i would put a wrench on the injector nut where the fuel line attaches to the injector. turn off the engine cooling water. have someone turn the engine over, quickly loosen the nut and watch for air bubbles. when the fuel is coming and no bubbles tighten the nut. then stop the motor. the motor must be turning to bleed the system. Then repeat the steps with the other injector. This should bleed out the air. It is important not to open the nut when there is no fuel pressure( the engine is not turning) because it lets air in.

i hope that is clear. then. start the engine and turn the water back on.

it is important to close the water intake when you are cranking the engine to bleed it, because it can pump water into the engine and then you got big problems. so right after you start it, open the water thur hull.

If you get no fuel out of the loose nut when the engine is turning them you have a problem in the system.

The little lever is the fuel pump, they work fine and if it turns out to be bad i would replace it. you can tell if there is no fuel coming out of it when the engine is turning over (same as above).

When you change filters you should change both of them, fill the container with fuel before you install the new filter and the engine will usually self bleed. the pump lever will fill the filter as mentioned above.

2. get an owners manual for the engine.

good luck

 

[petersea]

Not to be a smart remark but $150 is cheap enought if you can get the mechanic to "teach" you how to do it the first time. But maybe a dock mate or friend could help you or show you. It is not a difficult job so try it yourself (good instructions posted in archives and above post) and if all else fails get the mechanic to come out.

 

[Ed Schenck]

I was waiting for the answer to the "how long does it run question". I agree with above, Bob needs a manual and he should pay for a mechanic once. But isn't the motor a 2Qm instead of a 2Gm?

Here's my failsafe bleeding technique that you guys have seen me write about a hundred times here on HOW. Put a couple gallons of diesel in a clean outboard fuel tank, the kind with the squeeze bulb on the hose. Cut the metal connector off the hose. Clamp the hose onto the input side of the filter/water separator. Squeeze the bulb to build up pressure. Open the bleed screw on the(now clean) secondary filter until fuel escapes. Tighten and move to the injectors. Open each one until fuel escapes. This always worked on my old 2QM20. Ten minutes max.

Unless there is a lot of air between the tank and the primary the engine should run. If not then there was air, the tank is empty, or the fuel pump is faulty.

 

[garyc]

I installed a priming bulb the kind used on a outboard motor. A couple of pumps and it's primed.

 

[Steve C.]

I thought the H30's had YS series engines.

 

[Johnb]

I have had good results with the lever that is on the fuel pump. You just got to make sure it is'nt on the fuel pump lobe on the camshaft.

What I really logged on to say however is - do NOT NOT NOT crank the engine for too long with the raw water valve open because if you flood the exhaust it will ruin your year.

John Brecher

 

[qldman36]

. But isn't the motor a 2Qm instead of a 2Gm?

Ed and Steve c, why can't it be a 2GM?
My '79 27' has a 2GM init, but for sure it didn't come from the factory like that.[mucho money and labor can change many things]

 

[Steve Dion]

The GM series of engines came to market around 82 - 83. There is no telling what engines are in these old boats. There have been many engine swaps over the years.

The YS series was on the 70's boats and then they went to the QM series followed by the GM's in the midsized Hunters.

 

[Ed Schenck]

It could be anything that fit if it was repowered. I just wanted to suggest that he be sure so he purchases or reads the correct manual. It would be good fortune to have a 2GM in an older boat.

 

[gray125]

A similar thing happened to me this summer. It takes a lot of crud to clog the primary filter and I believe your problem may be further back in the fuel line. I would pull the fuel pick up tube and inspect it for blockage. It has a screen and it doesn't take much to clog and starve the engine. If it's blocked, clean it and get the gunk out of your tank and then proceed with the bleeding.

 

[bobsellie]

thanks everyone. Yes, she's been repowered to the 2GM engine. I'll put a pulb in line, leave the raw water valve closed, pump her up, bleed the lines, and let you all know. Thanks.
Bob

 

[bobsellie]

I installed a priming bulb the kind used on a outboard motor. A couple of pumps and it's primed.

Do you put the bulb pump before the filter/sperator, or after...or does it make a difference?
Thanks
-Bob

 

[Steve Dion]

I really suggest that you get it running without the bulb. Adding a bulb to your system just adds another place for your system to leak.

Get the system up and running again and then determine if you need the "BULB".

I have always been able to get our GM started after a fuel issue with the key and a wrench on the secondary filter.