oldsmokey97

One of my buddies has a '97 12v. Everytime you start the truck, it takes a while to start. You have to crank it for about 10 secs and then it will start but it spits and sputters and white smoke is pouring out of the exhaust. If you hold it to the floor for about another 15 seconds, it will clear out and run good after that. Here is a list of what all i did and checked.

1. lift pump is good fuel pressure is at 35 psi but it takes a little while to get there
2. lines from the tank to pump are good (even does it with fuel line coming from a 5gal can of diesel so its nothing in the tank)
3. overflow valve is new
4. injectors are good (i put in a set of my old stock ones that are fine)
5. fuel filter new
6. prefilter screen is clean
7. timing is fine
8. fuel shut-off solenoid goes all the way up and stays up

so, you see that there is only one thing left.... the pump itself

one thing is really weird though. i took the dv's out and when i broke the #1 holder loose and took it off the pump, diesel was flowing out of the pump for about 10 secs after i broke it loose. I have done many many dv jobs and have never ever seen this. Also, when you break the return lines off at the injectors, the first one you break off, diesel squirts out of it with a LOT of pressure. I have also never seen that neither. So, i changed the injector return line and the banjo at the filter housing and it does the same thing.
So, i am out of options except for the pump, but why does the return lines at the injectors have soo much pressure and why does the pump flow fuel out of it when you take a dv holder off??
One more thing, when i had the dv's out of the pump, and when you crank the truck over with them off, are bubbles come out of the #1 plunger.

Any help is greatly appreciated. Even the pump boys at Scheid are stumped.

Lance

RCW

White smoke is excessive unburned fuel in a cold engine. Long cranking times and then white smoke, and clearing after running it at high idle for a few seconds, would lead me to remove the fuel shutoff solenoid and wire the lever up and try it. It could be a bent linkage wire.

If that is not it, then check the injectors with a stethascope to be sure you do not have one or more that are contaminated with dirt. If you hear hissing or unusual snapping on one or more, they are full of dirt or rust. Real common
problem if the unused injectors were not properly sealed or stored wet.

After that I would pull the top of the pump and check the follower to make sure it is riding on the tip of the fuel cam as it should be. I would suspect it would be overrunning or stuck underneath the foot.

Lastly, if some moron removed the fuel cam and has let the rack slam against the pivot and has been driving it that way, then your pump is shot.

Ocmechanx

Right off hand what became of this cause mine is doin somethin similar?

dozer12216

should be able to blow through return line into tank(cap off). Think your truck should not have pressure on return hose. Look for pinched/restricted return.

Ocmechanx

Haven't had a chance to check everything yet to many other jobs just drivin the old diesel chevette I picked up for 80$

But when I filled the tank completly up it didn't do it but as soon as it dropped 1/8 of a tank it started again