Turbo Diesel Excessive BlowBy problems

[bratt]

i was wondering if any1 can help me

i just did an oil change on a 7.3 turbodiesel ford motor and im gettin excessive blowby through the crankcase

i looked for the pcv valve but i cannot find it?

should i try a different type of oil? what kind should i use? i put in the VALVOLINE Diesel blend 15-40 from autozone and its right in the middle on the dipstip. I dont have too much in there.

The truck does not have blow by at idle. i can leave the truck idling all day long and no problems. when i run it around 3 to 4rpm i get the blowby bad and it will stall the motor

[ModMech]

That oil should be OK, just be SURE it has an API rating of "CH" or "CI".

the 7.3L PSD engines are VERY durable, and given that the blowby at IDLE is not apparent, or a real issue, my *guess* is that the Catalytic converter (or muffler) are causing excessive exhaust restriction, and that is why it dies out at higher RPM.

[bratt]

well the reason i know its the blowby oil causing the problem is because i opened the air intake banks top and found oil in there by the turbo

and then i took off the hose going from the crankcase to the turbo and found lots of fresh oil dripping through the tube

at high rpms i get the blowby going into the banks turbo intake manifold and then getting burned out the tailpipes and also stalling the motor

i still dont know why i think its my oil. maybe i need some chevron delco 15-40 oil or the pcv valve is stuck open or something

i might change the oil tommorrow with some delco chevron crap

[bratt]

also at IDLE i get no blowby at all

only when i rev up the motor to 3 to 4 grand do i get blow by
i get a little at the high 2's

[Austin8214]

What is the red line on the motor?

[unclebubbles]

Sounds like you may have a combination of problems. Are you having to add alot of oil to the engine? When you reach the rpm where the engine stalls, do you see alot of smoke from the exhaust? Seems like it would take alot of oil to stall the engine at that rpm, and you would be low on oil pretty quick. As mentioned above, the stalling could be from an exhaust restriction. It could also be an intake restriction, or the turbo not spooling up like it should because a bearing is going out. The oil could be coming from a leaking turbo seal on the compressor side Theres nothing wrong with any of the oils that you mentioned, and i dont think the type or brand of oil is the problem.

[bratt]

yeah redline starts at 3 1/2 and goes to 4 1/2rpm
its a diesel!

and the turbo may need a rebuild. or maybe i'll take the cat off. i know im burning oil out the pipes and its coming out of that crankcase into the turbo i followed the oil all the way and its in the pipes and the turbo manifold

[bratt]

well i have a banks cat on the tailpipes and its not that old
i doubt thats it
theres alot of oil going through that crankcase hose to the turbo
too much

[bratt]

the weird thing is i dont see any oil consumption at all!

[ModMech]

What year is the truck?

Based on your use of the term "BANKS", I would guess that it is a 1993 or older vehicle, as Banks did not really offer anything for 1994 and newer 7.3L engines.

If you have an older engine, I would immediately suspect the "CDR valve", they are a know issue with older higher mileage engines.

The redline on the 7.3L is around 3400 RPM.

[bratt]

where do i find this cdr valve

and can i test it or do i just replace it?

[bratt]

ooh yes and its a 1992 model

[bratt]

what is cdr stand for

i tryed calling autozone and they said they dont show anything called CDR valve

[bratt]

today i took off the cdr valve

i think i have to order it from banks because autozone and pepboys dont carry it or know what it is

there was alot of oil in the cdr valve and in the side of the intake when the cdr valve is bolted

is that bad or is that normal

[bratt]

i tried some chevron 15-40 diesel oil but same problem so your right its not the oil

probably the cdr valve because it has a lot of oil in the intake and the valve itself

either that or my glow plugs are going out its white smoke coming out the tail pipes