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Help getting my om314 running.

11K views 12 replies 4 participants last post by  winmutt  
#1 ·
I spent all day trying to get it starting.

No fuel is coming out of the injector lines at the pump. We swapped out the glass bowl strainer underneath the pump, and pumped and bled until we found no more air was coming into it.

Still no fuel at the injector lines.

Started disassembling hoses for better inspection, when looking at the injector pump to the left of the bleeder (whats the screw for in the bleeder?) there is a banjo bolt. This is a bolt in a bolt, on the MW pump there is a spring and a ball in there to regulate fuel pressure, is there supposed to be a spring and ball in there on the A pump?

No more air seems to be coming from the return line, if I pump with the primer pump should fuel be coming out here?

I got one more day left in Miss to get this fixed, please help!
 
Discussion starter · #3 ·
But nothing about this double banjo bolt?
 
Discussion starter · #5 ·
I am referring to number 28 which is located on the pump right below the numbered one. We went to barry's u pull it in gulfport and found a CD (with burl wood!) and pulled the regulator from the MW pump. No luck on the pump we are going to have to tow it back so I can get it to the local injection shop. Can't get any fuel from the elements :(
 

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Discussion starter · #7 ·
Its the banjo bolt directly to the left of the bleeder.
 
Discussion starter · #10 ·
sounds like your primer pump..... cant pump.... so your moving no fuel or best worst case senario; there is a blockage inside either the primer pump or the fuel pump it is attached to. What you do not want is a blockage in the IP itself or a forzen piston in the IP.

again... have you bypassed the whole lift pump with an electric next to your tank? That will elimnate the two pre IP issues.

also.... I wonder.... does one have to turn the engine over to get any fuel out the IP injector lines. Pistons that build the pressure are in the IP..... if they dont move.... they dont build pressure and I would think they also dont move fuel. Would think you should get fuel out the IP overflow though when pushing fuel into it with a good primer pump or an aux. 12v fuel pump.
We ran on ether for a few seconds hoping fuel would come out. It could be a broken IP crank or just that it is sucking air in. Primer pump was working fine, plenty of fuel coming out and no air in the strainer glass or return line. Electric pump is on the list when I get it home. We have a good Bosch shop here and I am going to go ahead and try to source a replacement pump or atleast a full manual on the A pump.
 
Discussion starter · #11 ·
U back with the Motohome.....
No unfortunately not. Even with it running the brakes are going to need some serious TLC and it is just to costly for me to keep going down there and I don't like being away from family that much. And I *really* like drinking in NOLA :)
 
Discussion starter · #13 ·
The double banjo bolt is not a pump, it's a check valve to prevent the fuel from draining back into the tank out of the bleed circuit on the injectors.

Did you check for air leaks on the fuel filter cup seals? Sometimes they work like a one way valve admitting air into the system but no fuel comes out of them.

When you pump the primer, can you hear the fuel pouring back into the tank? If things are working right, you can pump until you get a consistent stream of fuel returning to the tank, stop for a few minutes, and pump once and it should squirt another stream from the return. If you have to pump a few more times it means air is leaking into the system from somewhere.
PES4A90 < A Pump.

There was no spring or ball in the double banjo. Any idea where I could get a replacement? Probably the local Bosch shop can do it when they put it on the bench.

Your description pretty much matched what I was seeing.