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rough idel, blue smoke, crankcase presure! help!

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truck seems to start really rough on idle and puff blue smoke, and oil is comming out of my breather baffel on top of my valve cover. whole under side of the truck is covered in oil now. seems like i have alot of crank case presure.. rear main is starting to piss oil now too. could this be a injector? bad vacume leak..? if you may think so whats the best way to find out? sea foam?

thanks guys!
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Yes but also an injector causes this issue. Take to a shop and do an injector leak down test. With truck running pull oil cap off and look at the blow comin out oil fill. If it's puffing like a freight train more than likely injector fried cylinder overheated and melted rings. My guess number 6 or number 4. Maybe more than one. Good luck.
 
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high crankcase blowby pressure will cause motor oil in the turbo to be forced into the housing, exhaust impeller side if your lucky resulting in blue oil smoke out the tail pipe. if you're unlucky, the oil squirts into the compressor side and the engine goes into self destruct runaway mode burning motor oil along with diesel and NO WAY TO SHUT HER DOWN.
:eek:noz::turbo::titanic::kaboom:
SHUT HER DOWN JOE, SHE'S A SUCKIN' MUD.

high oil pressure will also destroy your crank seals quickly from forcing them out against the crank at higher pressure.
 

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Being an optimist maybe the oil running down the back of your engine is from what you saw leaking at the breather.

An injector alone will not cause the blue smoke unless somehow it has fallen out or catastrophically failed and some cylinder head oil is making it into the cylinder and that would make all kinds of noise when the piston comes back up.

If your really lucky you could have a head gasket that failed between oil passage and cylinder but I doubt that.

I'm assuming when you take the oil fill off you see lot's of oil mist gasses or something.

Seems more like ring's and or piston caused by an injector which is fairly common.

I would send the injectors out to be tested as one probably caused this then pull the head and you'll know exactly what's going on.

"Seafoam" :shock: Damn they have done some good marketing.
 

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Discussion Starter · #6 ·
thanks alot for your input guys! thinking out side of the box.. if it was a ring or piston wouldnt it consistantly blow blue? this is only on start up, drive it for 10seconds it goes away..

also the oil is comming from the baffle where the tubes conect and out of the oil fill.. dosnt crank and crank to start either, it starts fairly well.. like any cummins
 

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a HPCR Cummins 5.9 with good injectors, batts, cables and starter will fire off in less than 10 revolutions.
mine starts faster than most fuel injector newer gas engines.
 
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