loosing prime

M

mopartechnician

Alliance Diesel
Joined
Nov 19, 2008
Messages
27
Hey on my 02 cummins 6speed, when I let it set for like an hour, I go to start it and it will start fine but it blows out a big puff of white smoke and the engine sounds like when you are bleeding the injectors (that real loud dieseling sound) I got a raptor 150 feeding 18psi to the injection pump last time I checked. No codes. Im thinking that its somehow bleeding the fuel back. I really can''t think strait right now because I really can't be having my truck running like **** right now. After you run it for a while it runs fine and starts fine. Ive pulled the fuel filter out and check it and the oring, they are fine but Im gonna change them anyways tomorrow since its cheap. I have change the banjo bolt on the vp44 supply line with a normal one and new washer seals (the old one had the schrader valve wanted to eliminate that just incase). The only thing I can think of right now is either connector tube orings or injector orings. There are no fuel leaks, Im thinking that somewhere air is getting in, I will hook up a gauge tomorrow and see what happens when I start it and it acts up. No codes, reman injeciton pump at 85000 truck has 93000 on it.

Any thoughts would help,

thanks
mopar
 
if it starts quickly it doesn't sound like it's loosing prime! it would be hard to start! it could be a weak injector, as for the white smoke, how cold is it? the grid heater might not be working correctly or could be unhooked
 
it doesn't matter how cold, it actually got to 65 degrees yesterday and did it, the heaters are working, I have a set of stock injectors I might try putting in and see what happens, Im gonna put new injector orings and connector tube orings on at the same time so I won't know which one fixed it if it does fix it, guess I will have to send off the injectors and have them tested.
 
Check the return on the line on the back of the head. I had the same issue and I found some fuel on the top of the trans. Once I snugged the line up it started fine.
 
also if you illiminate the fueling option then my truck did that everytime hot or cold when my head gasket started seaping. It was seaping water into the cylinder and everytime I started the truck I got white smoke and a weird rumble.

Could be getting water from a badly cracked head.

Lavon
 
I'd replace the o-rings on the connector tubes first. I had something similar happening to me and it turned out to be a bad one.
 
Alright, tested the return line pop-off and its working fine, checked the return fitting on back of head its good. Parked the truck this morning with the nose downhill started it like I usually do, blew out a huge cloud of grey/black smoke and shook real bad, when driving the truck it will blow out a trail of white smoke, so Im starting to think I got a bad injector. Got injector o-rings and connector tube o-rings comming, have two sets of stock injectors in my garage so gonna do a quick swap, if that doesn't fix it, gonna swap out the injection pump.
 
For peace of mind take one set of injectors by and have them checked out, it's cheap insurance if they have been siting on a shelf for a bit.
 
swapped out injection pumps, still acts up, might do an injector swap tomorrow real quick and see what that does, had my buddies smarty on there today on level 9 and was getting a miss at idle, so maybe signs of a bad injector. HOPEFULLY, just kinda throwing parts at it until that check valve comes.

I don't have anybody close that can check injectors, the closest place is 2.5 hours away, so Im gonna take a chance that they are good, they were in my buddies truck and we just removed them to put 150's in
 
Last edited:
well I thought it was still acting up, went out the next day and started it to pull it in to do injectors, started up just fine, its been two days now and it hasn't acted up once, its a s.o. pump on a h.o. engine so Im gonna have to get the h.o. pump I gave to my buddy a year ago back since he has a 5speed and doesn't need the h.o. pump.
 
You must log in or register to reply here.
Back
Top