provent 200 instead of cdr?

[Nosferatu49534]

If the provent/cdr is to "recycle" (I use that word loosely cuz I'm still trying to wrap my head around this) would it be just as effective to basically run a tube from the hole in the valve cover for the cdr to say the turbo drain hose so the oil could flow back in? Or is there some other voodoo I'm still not getting?

This is all very interesting by the way.

 

[ak diesel driver]

Needs the vacuum created by the turbo to pull the crankcase gases out. Oil drain would make it a closed loop with no vacuum source.

 

[Will L.]

So to continuing after AK...
The vacuum from the turbo pulls vacuum for the provent (think oil catch can). The vacuum draws the pressure out of the crankcase, along with some oil in mist form. Then there is a "filter media" that causes the incoming oil mist to coalesce and drip to the bottom of the can. This oil can be poured back into the oil fill at your liesure manually (based on how often it fills up) or it has a drain that returns to the pan.

The idea of draining down LIKE the turbo is correct, however NEVER tie up the turbo drain with anything. Backing up the flow of oil coming out of the turbo could be the end of the turbo. It does need a check valve for the return oil. This mainly is to keep the oil flowing the right direction incase of really big bumps or angles.

 

[FellowTraveler]

Notice, the provent and other aftermaket crankcase vents/filter systems are sized according to engine output while the CDR on the GM 6.2/6.5 stays the same size, I suspect there is more to this we/I need to learn about. Guessing here, but perhaps two CDR's or a properly sized aftermarket vent/filter on the 6.2/6.5 is a better option all around.

There is at least one 6.5 td on this site that need's a bigger PROVENT than the 200..IMO.

I did try a remote crankcase catch can/filter w/CDR and developed a front main seal leak went back to GM setup and leak stopped.

I'm considering a PROVENT to eliminate the open vent tube on the Cummin's 5.9.

 

[Nosferatu49534]

Basically they're both not allowing gases back to the environment, and the provent returns oil through a separate drain instead of back down the valve cover, if I understand correctly.

 

[Will L.]

@FellowTraveler : not just 1 cdr for all 6.2/6.5. The 6.2 uses one, the n/a 6.5 uses a different one, the 6.5td uses a third. The p400 in the upfitted hmmwvs that I have seen uses a different one than those 3, hut is in a different location, so may be interior same just different hose connections.

As for the different size provent, the 200 is 200 liters of blowby per minute. The 400 is 400 liters of blow by per minute. The hp rating is a General rule of thumb for volume estimates. A 6.5 liter engine that maxes 4,000 rpm would use the same provent regardless if 200 hp or 500 hp.

@Nosferatu49534 the difference is, if you look in the intake tube after the point of connection for your cdr, you will see there is oil there. This is the oil mist getting sucked through the turbo and down past the intake valve, and getting burned.

While a little oil going through doesn't hurt anything other than maybe a little extra carbon build up in the cylinder, when you have some descent wear on the rings, the amount of oil you consume will begin to add up.

The provent captures all of the oil and returns it to the place it belongs. When I said return to the pan, I dont mean it is closer to the bottom of the engine. If could return into the valve cover if you mount it high and want it to return there. I meant not burning the oil, but returning it as lubricant instead of fuel.

 

[Nosferatu49534]

@FellowTraveler : not just 1 cdr for all 6.2/6.5. The 6.2 uses one, the n/a 6.5 uses a different one, the 6.5td uses a third. The p400 in the upfitted hmmwvs that I have seen uses a different one than those 3, hut is in a different location, so may be interior same just different hose connections.

As for the different size provent, the 200 is 200 liters of blowby per minute. The 400 is 400 liters of blow by per minute. The hp rating is a General rule of thumb for volume estimates. A 6.5 liter engine that maxes 4,000 rpm would use the same provent regardless if 200 hp or 500 hp.

@Nosferatu49534 the difference is, if you look in the intake tube after the point of connection for your cdr, you will see there is oil there. This is the oil mist getting sucked through the turbo and down past the intake valve, and getting burned.

While a little oil going through doesn't hurt anything other than maybe a little extra carbon build up in the cylinder, when you have some descent wear on the rings, the amount of oil you consume will begin to add up.

The provent captures all of the oil and returns it to the place it belongs. When I said return to the pan, I dont mean it is closer to the bottom of the engine. If could return into the valve cover if you mount it high and want it to return there. I meant not burning the oil, but returning it as lubricant instead of fuel.

Makes sense to me now. thanks.

 

[WarWagon]

IMO Blowby doesn't affect the amount of oil burned till the oil control rings "completely fail". The harder you work the engine and hotter the heads get from the workout the more oil you suck out through the CDR. ~1 quart every 500 miles is the upper limit and IMO average for my 6.5's. New rings or "on fire blowby' engine had the same oil consumption for me. I use a quart every 1K likely due to bad valve stem seals. High load high RPM (tached out) last time I went to CA without a trailer had scary high oil consumption.

Some have gone back to the 6.2 CDR that pulls the fumes out of the oil fill vs. the hot valve cover. You need the oil slinger baffle put in around the chain to do this.

Road draft tubes... The "new" engine oil simply "Stinks" like a refinery. Some stink longer than others. (1000 miles reduces the odor on some.) Makes me want to slime the intercooler on my 2003 Dodge by putting the road draft tube into the intake. The screwed up HVAC intake leaks don't help the situation on the Dodge requiring extensive sealing...