A guy I know had a stock injector break on his 01 (auto/SO pump) last week. It started running rough, pouring whtie smoke, then the oil filled with fuel and it puked every where. Turns out half of the tip of the #3 injector broke off, a very small piece, small enough to escape thru the valve.

He puts a set of new 60hp stick in, changes the oil and fires it up and now it has a very rough lope at idle like its running on 5 cylinders. No metal scraping, knocking or other internal sounds. So I cracked some injector lines to see what happens, on 1,2,4 when i crack the line the motor gets REALLY rough. But when I cracked #3 the motor sound doesn't change one bit. Is it possible that when the tip broke off, that lack of pressure at the injector could have damaged the VP44 where it meters the fuel for cylinder #3?


Also another side-affect is now after having all the blow by puking out from the fuel in the oil, the motor seems to have a large amount of vapor blowing out the breather bottle or oil fill cap when you take it off. Any idea whats causing that?

 

The injector tip may have caught a valve on the way out the motor, bending or knicking it. That could cause the crankcase pressure issue.

 

well the tip could have done numerous things in the cylinder, serious scoring causing blowby. i doubt the IP got hurt now like what was mentioned if the valve is chipped or you got bad walls then you're not getting any compresion and your just dumping the fuel which is why your not noticing a difference in the sound of the engine.

 

Yup , C2O got this one on the nail... Might me time for a rebuild!

 

I would take the valve cover off and start the engine. Don't rev the engine, just let it idle and watch the rockers and the valves for a few seconds. If you notice the valves on that cylinder not moving as much, then you might have a bent push rod which will cause the engine to run just the way you are describing. I swaped out injectors on mine and didn't pay attendion and one of the push rods wasn't seated in the lifter/tappet. It bent the push rod making it run rough with lots of white smoke and when I cracked the injector line to that cylinder it didn't change the sound.

If this is the case, make sure to check the tappet with a flash light to see if the cup on top of it is chipped. also, I would really think about taking the head off as there is most likely damage to the piston, piston walls, valve(s), and head.

 

When we cracked open the line on 1,2,4 we got a trickle of fuel, and it pusled like the injector opening. On #3 we got a steady stream of fuel out with higher pressure the the others and there was no pulsations.

If the fuel was just dumping due to no compression(hole in piston, scored walls etc) Wouldnt I notice a rise in the oil level again and more white smoke? The smoke is nearly gone and the oil level is staying right where I filled it too.

Rick

 

Maybe the pump was the cause of the orginal failure!

 

Also this problem didnt just happen instantly....It gradually happened over a 20mile trip. Started with a odd sound under aceleration thru the stacks to a white haze from the stacks to a definite miss and pouring white smoke and then to oil pouring out of the crank case breather.

Rick

 

Definately damage to the cylinder, possibly a valve got damaged as mentioned, but I'd say that when the tip broke off the injector filled the cylinder with fuel & washed the hole out. I'd do a compression test. Did you check the turbo for damage? If a piece that big got through, it probably damaged the turbo.

 

What sticks were they??

 

My guess is like others that there is some internal damage in the hole. Either a piston, valve or cylinder wall, something is leaking.

Oil pouring out of the breather would be caused by the crankcase filling with fuel or compression forcing the oil out. Either way, not good.

I would assume you drained the oil when the injctor was swapped? Or was the level high?

Dave

 

i totaly agree i had a pump die on a friend of mines 01 and it destroyed 2 of his injectors and never threw a code until after we changed sticks and he drove it a few hundred miles when the shop got the pump they said it came apart and thats what took out the injectors. and ive seen this happed more than onece..

 

Is it throwing any codes?

 

no codes but i am gonna try to get ahold of a used (but working) vp44 for Rick, it would be much easier and cheaper to try that first before we go tearing into the motor.

how come so many 3rd gens can have an injector stick open, fill the crank case with fuel and not lose a cylinder but it seems that 15-20 miles may have wiped this one out. and there is no internal engine sounds like something is wrong, if the cylinder was washed wouldnt there be some piston slap?

 

Well it could still be dirrectly related to the Fuel issues, And may have not caused any major damage (Cross your fingers)! Most of the common rails that get washed down do eventually have major problems...and the duramaxes..... for the most part, I belive everyone here is speaking of the peice of the injector causing problems! Another big problem that could cause injector problems would be high Cyl. Temps or pressures , Related to The timing being off ?