5.9L Rotary PerformanceDiscussion of 12 Valve 5.9 Liter Dodge Cummins Diesels with Rotary Injection Pumps Related To Performance And Longevity
Thanks to RSWORDS for the cool walbro fuel pump install write up. I followed his example, put a draw straw in the tank, installed the pump, Mallory fuel pressure regulator mounted near injection pump with the boost attached, ran it all to a newly rebuilt ... JOIN NOW TO REMOVE TRACER
Thanks to RSWORDS for the cool walbro fuel pump install write up. I followed his example, put a draw straw in the tank, installed the pump, Mallory fuel pressure regulator mounted near injection pump with the boost attached, ran it all to a newly rebuilt injection pump with a fuel pressure gauge plumed in right at the fuel inlet to the pump. The problem I've run into is after the truck sits overnight, or even as long as 8 hours, it's hard to start. It has to crank over 8 to 10 revolutions before it will start. After it's started i can shut it off and the truck will fire right back up before it even cranks over. I have 13psi at the injection pump, and no leaks. Whats the deal with the hard start? Is the fuel pressure to the injectors bleeding off overnight or are my injectors bad? I replaced the entire fuel system, including the injection pump, lines and all. Cant figure it out!
Yeah, the injection pump was just rebuilt by a local bosch shop about 2000 miles ago, and the walbro pump is new. The only line I reused was the return line from the injectors. But I dont see any fuel leaks.
Question after you start it and shut it off does it start right back up or crank over and over again? Try somthing crank it over and hit the loud pedal and if it fires right away it might need timing advanced and it sounds like it might be leaking off to but where i dont know
After I get it running the first time, it will fire right back up with no hesitation unless I leave it sitting for several hours...like 4 or more hours.
come to think of it, I had this same problem before I replaced the injection pump...but I just thought it was due to a bad lift pump. Now that I've replaced and bypassed all that it must be that return line from the injectors. Is it possible to have an air leak without seeing fuel? If I cant get to it real soon, will it hurt anything to continue running like this for a while?
Last edited by butcherman; 07-13-2010 at 08:21 PM.
Reason: Automerged Doublepost
Did you ditch the whole fatory fuel filter and lines?
As others have said it sounds like you have air getting into the lines and it's draining back. Go over everything you have put in and make sure it's tight.
And yes you can suck air with out leaking fuel.
If you still have the factory filter setup I'd start at the fuel heater gasket.
Good Luck these problems can be a PITA
it wont crank that long i had my psi on my ve pump at 15 with my airdog and not the slightest hesitation. when i did my p pump swap my truck did the same thing yours is doing, until i found the return line leaking a little bit. tightened it up and never did it again
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