I want to take drain tube off my 2000 to either clean, or make new one for it as I still am have minor oil blow through from new turbo. I seems to only happen when in 3rd and 4th gear, not under heavy load.

My drain tube seems to run between exhaust manifold and a heat shield. Please tell me I dont have to take off manifold to get that #)*$)#* thing out of there.

Probably not the drain, most likely normal CDR (see FAQs how that works) or a bad CDR causing excess, what exactly you seeing on 3-4 gear shift, sounds like normal fuel smoke puff all of us get when changing gears, heavy or lite smoke & what color?

the big problem is the hole in the block to return the oil is barely over 1/4". try a restrictor in the feed line.

It's definelty whitish smoke. It's not there under heavy accelleration, not even there under slow accelleration, but as soon as truck shifts to 3rd or 4th the whiteish smoke begins. It seems to be RPM/ torque related but that makes absoluetly no sense. One other thing I have my CDR venting to catch can, does the CDR create some sort of vaccum to aide with evacuation when venting back into turbo snorkel. My catch is pretty full also.

What is purpose of CDR valve. If I have mine venting to catch can which I noticed tonight is a mess, I know the whitish smoke can't be from it. Does it relieve pressure from crank case like a EGR on a gas engine. But again even if bad still can't be cause of whiteish smoke. Still confused why smoke doesn't occur under heavy load or accelleration. Why does it occur when boost start to decrease after engine goes into lower gears?

The CDR is crankcase depression regulator, vents crankase pressure over 1psi, and does not allow the turbo to suck the crankcase to more than 1"Hg vacuum.

Sounds like the smoke is from late timing rather than burning oil. Hook a scanner up and see what CTIME, TDC Offset, and watch DES ACT timing as well.

OK so I have my CDR venting to catch can which is an absolute mess. And smoke out the back is definetly oil not fuel. So couple questions if CDR is bad does that mean it will not allow venting of crankcase? I don't think that is the case thought since my catch can is an absolute mess it apprears to be either venting right away or not venting till a higher psi pushing oil past rings possibly? I will hook up scanner this week or this weekend when I can get to friends house.

Another not somebody stated that oil return hole in block is restriction in oil return. Is there a way to fix that, I've been thinking of taping pan for oil return much like some of my high performance turbo buddies. Anybody try that?

Here's the oil retrun over the mechanical fuelpump slot.

TJ did you read in FAQs how CDR works, there is a test in there IIRC how to see if operating correctly. Heavy oil out the tail isn't common, start with CDR tests, if all is happy there you may & read may; have something more of a mechanical nature going on, what is your oil consumption rate?

It seems to be using about 1/2 - 1 qt every tank of fuel. I'm getting about 400 miles to a tank of fuel. I will read how to check CDR and do test. What about valve seals leaking creating a little vacum while off throttle or boost?

That would create pressure in the crankcase not vacuum. It does seem like you're using oil like you have moderate blow-by and you're burning it through the CDRV which it's designed to do.

CDR is closed-system operation - dipstick sealed, oil filler cap sealed, no other breathers in system.

Build the simple manometer, check the system out - can be done in PARK, with someone to rev the engine up to 2000rpm while you observe the manometer.

CDR system must be in original oem configuration to pass the test.

Which one designed that drain tube going into the block like that? Goofey or Mickey?

My thoughts exactly. I have threatened to "sock" some GM engineers in the mouth lately, after digging into some of this stuff. : )

GKCTD

What is a Manometer? And what should it read?

Actually (he said) - that is a very good location - max distance below turbo for excellent gravity drain, yet above max oil level in pan, with a barrier between that crank-splashed oil and the drain inlet.

High veocity turbulence from timing set\chain rotation provides some added help in pulling frothy, low density oil down into the crankcase.

Solid, cast iron mounting, so vibration cannot crack silver-soldered joint in oil pan.

I can think of no better location for it, eh?

But, then again - I have been called both..........................;)

CDR in FAQs....................

Actually (he said) - that is a very good location - max distance below turbo for excellent gravity drain, yet above max oil level in pan, with a barrier between that crank-splashed oil and the drain inlet.

High veocity turbulence from timing set\chain rotation provides some added help in pulling frothy, low density oil down into the crankcase.

Solid, cast iron mounting, so vibration cannot crack silver-soldered joint in oil pan.

I can think of no better location for it, eh?

But, then again - I have been called both..........................;)
And most important, it's already there!

I was more so refering to the chicken **** hose and clamp system, a braided line would have been much better to screw on/off at both ends.

As is true in many relationships, it is a matter of size - in this case tubing i.d. to o.d. and available space.

Pull the pressure hose off the top, check the diameter available for actual flow, compared to hose o.d.

The large i.d.of the return line is required because the return oil is a frothy, low density effluent, passing down the line by gravity drain.

Factor the i.d \ o.d. of that nice stainless covered teflon line, to get a sense of the requirement for the 1" drain return line.

And, the price............

I can get line cheap enough (if you know what I mean) I can't seem to get that damn factory tube out of there without taking mainifold off it appears

Un-bolt the drain cover from the block, loosen the clamps on the rubber hose, remove bottom section, only - should give some idea if lower end or block is plugged.

Well aren't I an idiot. I could have done that this weekend

Ahhh, so unlike what the wife says, size really does matter.:blahblah: Not that we're listen though... ):h

You mean that wiggling the worm thing means nothing?? Blahhhhhhhh

Some fish do quite nicely, using that technique!

But, long green is the great equalizer, I think..........or, really big plastic.......