yanmar 4 cyl diesel not getting fuel

[Cory9584]

I'm helping a friend fix his tractor thats been sitting. I can prime the thing all day and i still hear air inside the pump. I tried bleeding it from the end of the small line that goes to the injectors and the primer started to feel a little tighter after a while but then i tried cranking it and the primer got soft again, and i started getting air all over again. Later i tried taking the line off the primer and putting my finger over it while i pump it, then i noticed theres hardly any pressure coming from there? is that normal? The filter bowl fills up but i think theres just not enough pressure to bleed the system correctly. Does anyone have any tips on getting this thing going? Thanks

 

[Plyscamp]

What style of fuel pump does it have? If it is the small diaphram pump like they use on the Duetz, Catapillar and others. I have had good sucsess replacing them with an electric automotive pump. Also makes it much easier to prime if you run it out of fuel.

 

[dingeryote]

I'm helping a friend fix his tractor thats been sitting. I can prime the thing all day and i still hear air inside the pump. I tried bleeding it from the end of the small line that goes to the injectors and the primer started to feel a little tighter after a while but then i tried cranking it and the primer got soft again, and i started getting air all over again. Later i tried taking the line off the primer and putting my finger over it while i pump it, then i noticed theres hardly any pressure coming from there? is that normal? The filter bowl fills up but i think theres just not enough pressure to bleed the system correctly. Does anyone have any tips on getting this thing going? Thanks

Fill the tank and try it again with all 4 injector lines slightly open at the head, and prime untill the fuel runs out at each without bubbles.

Crank the thing over a few times if your thumb ain't gonna make it.

Gravity pressure from a full tank alone helps a lot.
Those primers don't make diddly for pressure.

Some JD/Yanmar have a bleeder on the injector pump itself, so if you strike out, start going upstream looking for leaks/blockage.

As a last resort, and to save starter wear, a small snort of Ether helps if the lines are REALLY empty.

Good luck to ya!
It can be maddening as hell, just stay with it.

Stay safe!
Dingeryote







There also should be a

 

[Cory9584]

you dont think theres another filter somewhere underneith by the tank?

 

[DHIBBS75]

1 make sure you have fuel to the transfer pump. If there is a filter between it and the tank make sure it and the lines are not plugged.

2 make sure the line from the transfer pump to the injection is not plugged or calasped if rubber.

3 crack one or more inj lines loose, one will do. spin the engine till fuel starts coming out and if you leave at least one line tight it should start... or start smoking....

If all else fells gas on a rag in the airfilter is much easier on the engine that starting fluid......

If you have fuel to the injection pump but none out you have a stuck rack in the pump...

Good luck.........

 

[Cory9584]

I'm trying to get a better understanding for this. on the injectors you have the 4 larger individual lines that go to the pump, then theres a single smaller line that goes to all of them. on the end of the smaller line theres a cap (i was getting fuel to this point in spurts). What is the pourpose of that small line? I thought the pressure came through the larger lines and the small one was only a return? Am i right?

 

[DHIBBS75]

The small line is a return line to the tank or pump or filter base. dont worry with it...... The line that needs to be broke loose are the larger steel line with usually a 3/4 or 11/16 wrench or metric...... 16,18... crack only 1 or 2 loose...