Need more help - priming fuel line Hunter 30

[John North]

I would like to thank the person who wrote to me in an earlier article. I did indeed find a blocked pick-up hose inside the fuel tank and now have fuel entering the primary filter. I still have to get fuel from there up to the engine filter and into the injectors. I have tried to prime the lines by manualy pumping with the lifter but I cannot get fuel to come out of the bleed on the top of the filter.I feel that I am being defeated by this experience. There is obviously something that I do not understand. I have read the Yanmar owners manual and it deals with this in a simplistic fashion. I still don't see how the fuel is pumped. Is it mechanical or is it drawn further by vacuum? Please leave an email address so that I can thank you again.

 

[Douglas]

Try moving the

the crankshaft a half turn and see if you can get more movement at the fuel pump lever. The pump is worked by an eccentric and it may be at the upper position, limiting the amount of movement when you try manually to move it. Be sure to check your manual and turn the crankshaft only in the direction stated. I have replaced the fuel filters on my 89 H30 and had no problems bleeding the system by the pump lever.I am not the same person that originally posted to your question but hope this info will help. Have patience - it is a learning experience.-DougS/V Brenda Gail

 

[Paul Sealock]

Shut off Valve on top of fuel tank

Check to see if you have a shut off valve on top of your fuel tank. It may be in shut off position.Some times it a simple thing.

 

[Paul Akers]

Crank the engine

I changed my filters this weekend. What I do is have someone crank the engine while I loosen the bleeder screw on the filter housing. The air will bleed out of the screw until the fuel reaches it. When you see air bubbles stop coming out and only fuel, close the bleeder screw. The engine should then start. It's possible to get air further up into the line also. In this case, while the engine is running, crack the nut on the fuel line at each injector (about 1/4 turn), one at a time, starting with the injector closest to the fuel tank in the line. The engine will shutter, but when the air bleeds out, tighten the nut and it will smooth out. Repeat for each injector in line. Then I let my engine run long enough to ensure that there was no air trapped in the line (about 15 mins). If there's air, it may stall.

 

[Bryan C.]

Bulb pump

Do yourself a favor and buy a bulb pump like the kind outboard motors used. I think the 5/8" version fit my 3GM30F. Make bleeding so much easier than the little inefficient lift pump. I have read on other ocassions that the lift pump won't work if the crankshaft is at a certain orientation. I put the squeeze bulb between my primary filter and the engine lift pump by cutting the line and clamping it on with hose clamps. The bulb is very powerful and will usually bleed it with just a few squeezes. The pump (lift or bulb) creates a vaccum which sucks the fuel in, so if you have do not have a secure fuel line (ie air gets can get sucked in) it won't draw fuel. I was reminded of this when I changed my filter last weekend and left the fuel drain unscrewed on my little Racor (looks backwards from what you'd expect). No amount of pumping created any fuel flow because air was getting sucked into the system thru the Racor fuel drain. After I tightened back up a few pumps on the bulb sent fuel shooting out the bleed screw on the secondary filter and onto my shorts.