blowby smoke out my vent

[JRODS*LB7]

Ok im getting excessive blowby out of my vent ,no fuel in my oil,my upper coolant hose isnt rock hard,But my #6 injector balance is reading 8.03 and #7 -2.35 this basically happened over night truck was running fine yester until i started it this morning and heard my injector knocking what im trying to fig out is why i got blowby could it be oring on #6 injector and would tht through the balance off?

 

[Bustedknuckles]

Check compression......

 

[paint94979]

Sounds like a bent rod

 

[JRODS*LB7]

Sounds like a bent rod

a bent rod? i only got a 150hp tune wouldnt a bent rod cause a rough idle?this truck idles smooth no loss of power at all i will check the compression though

 

[ecc_33]

Yea bent rods do have rough idles and white/gray smoke when idling. I would say its a injector problem.

 

[JRODS*LB7]

Yea bent rods do have rough idles and white/gray smoke when idling. I would say its a injector problem.

Thats what i fig. like i said truck idles so smooth no smoke out the tailpipe oil pressure 60psi at idle then drops to 40 when warm, almost 80psi cruising,no fuel in the oil yet,and no pressure in the cooling system.So thats y i am wondering if its a oring on the injector or a cup but if its a cup would i get coolant in my oil?

 

[ecc_33]

If it was a cup you would have major presssure in the coolant over flow tank

 

[ecc_33]

usually blow by is caused by crankcase pressure. I would do a compression test to make sure you don't have a hole in a piston. How much blow by are you talking take the oil cap off with it running and see how much is coming out of the cap

 

[JRODS*LB7]

If it was a cup you would have major presssure in the coolant over flow tank

yea im pulling it out tommorow im willing to bet its an o ring

 

[JRODS*LB7]

usually blow by is caused by crankcase pressure. I would do a compression test to make sure you don't have a hole in a piston. How much blow by are you talking take the oil cap off with it running and see how much is coming out of the cap

when i take the cap off its not a steady puff its more like a choo choo train light haze smoke not like oil buring smoke crazy amount of smoke kinda a light haze puff puff just enough to be noticeable

 

[jneal]

yea im pulling it out tommorow im willing to bet its an o ring

There is no o-ring anywhere in a duramax that keeps compression from entering the crankcase and causing high blowby.

 

[x MadMAX DIESEL]

Sounds like a bent rod

this causes blowby?

 

[Bryce418]

Sounds like there might not be anything wrong. Crankcase pressure will fluctuate like that. Anything causing any noteworthy blowby would be pretty noticeable.

 

[Bryce418]

this causes blowby?

Not that I have ever seen, but it sure shows up in the balance rates!

 

[Mikey]

could be a ring

 

[02greysixer]

Is this new or did you just take the cap off messing around and see that it does that? I get a little bit off mine, it's just the nature of the engine since lb7s don't have a pcv system. If you're really worried you could take the crankcase breather hose off of the alternator bracket (down by the fuel port under the alt), hold your finger over it and take the oil fill cap off. Then flip the oil cap upside down and set it on your oil fill pipe, if you have enough crankcase pressure to blow the oil fill cap off the pipe then you've probably got a problem. If the cap doesn't move then I wouldn't be to worried about it. This is just my opinion though :thumb:


Sint frum tha orijinul smert fone

 

[JRODS*LB7]

Is this new or did you just take the cap off messing around and see that it does that? I get a little bit off mine, it's just the nature of the engine since lb7s don't have a pcv system. If you're really worried you could take the crankcase breather hose off of the alternator bracket (down by the fuel port under the alt), hold your finger over it and take the oil fill cap off. Then flip the oil cap upside down and set it on your oil fill pipe, if you have enough crankcase pressure to blow the oil fill cap off the pipe then you've probably got a problem. If the cap doesn't move then I wouldn't be to worried about it. This is just my opinion though :thumb:


Sint frum tha orijinul smert fone

yeah this just happened as far as the noticeable haze coming from the vent tube and the injector knock theres deffinately not nearly enough pressure to blow the cap off when i turn injector 6 off the knock goes away but still haze's from the vent tube!Correct me if im wrong guys but if it wer a bent rod,hole in piston,bad rings wouldnt the truck idle kinda rough? Oh and by the way im not buring any oil either.

 

[JRODS*LB7]

There is no o-ring anywhere in a duramax that keeps compression from entering the crankcase and causing high blowby.

well i guess il see tommorow because it seem #6 is the problem area

 

[JRODS*LB7]

pulled it apart today and found the culprit,a loose #6 injector...SOB. also found a rivet just sitting in the head along side one of the pushrods,i have no clue how that got in there i dont even have a single rivet in my garage???? anyway its allset now:woott::thumb:

 

[Noreaster]

good to hear that it wasn't anything major