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If CCV means crank case ventilation, what, then, does PCV mean?
CCV is Closed Crankcase Ventilation, a completely different concept than the '60's acronym and concept PCV, for Positive Crankcase Ventilation, crankcase being a one-concept word
- PCV utilizes a filtered breather port on one valve cover, usually connected to a filter in the air filter housing, with a 'nuther port on the opposite valve cover connecting the crankcase directly to the hi-vacuum intake on those other engines - this allows positive flow-thru from atmosphere to evacuate the oily vapors for consumption in the cylinders, neb'mind about creating any vacuum in the cc - the PCV valve limits applied vacuum at incident of extremely hi vacuum, such as decelerating from freeway speeds down an off-ramp to a traffic lite at the underpass to prevent pulling excessive raw oil outta the contributing valve cover - the longest cc effluent path, valve-cover outlet to intake, is usually less than 10", so not much opportunity for liquid mist to precipitate out of the hot vapors - not only that, but in those systems the fuel charge is trucked in with the intake air charge, thus having a solvent-like tendency to continually wash the oily mess from the intake plenum
- CCV, used on Diesels, has no port to atmosphere, instead allowing any vacuum developed in the turbo inlet tract to maintain a constant slight vacuum in the crankcase, which allows the pistons to reciprocate easier, also aiding crankshaft seals and other sealing areas - any oily vapors from super-heated (avg EGT 650*F) engine oil and all piston-ring blowby is drawn into the compressor inlet, heading for the cylinders - however, the hot oily cc effluent path is at least 12" from the CCV puck to the compressor inlet duct, another ~6" thru the centrifugal compressor (and, we all know what centrifugal forces do to heavier components in gasses, right?), another ~24" thru the outlet hose to the charge air cooler inlet, another ~24" thru the cac, another ~ 12" from the cac outlet to the intake manifold inlet, thence thru the plenum and finally to the cylinders - quite an extended voyage, indeed
Now, far be it from me to nitpick, but it seemeth to moi that, in a crankcase-effluent distance-traveled competition, the KJ CRD would win, hands down, over a KJ with one of those other engines - not only that, but, iirc, Science 101 was fairly explicit in explaining many of the laws we must needs live by, one of which details how the process of removing heat from a gaseous vapor usually results in any liquids in that vapor(s) quickly condensing and precipitating out, coalescing amongst the walls along the system containment path
Thus and so, it would seem very unwise to compare a '60's PCV system for gassers (patooie!) to a '90's and beyond CCV system for Diesel engines, being two very different implementations of a concept, particularly considering the distances between crankcase port and combustion chamber in each system - it is, therefore, my considered opinion that a charge-air cooled turboDiesel engine absolutely requires a Provent\Racor\equiv filter be installed to augment the factory CCV system - unless, that, is, you're anticpating really hard times ahead, and those oil reserves in yer intercooler will sure come in handy when the economy goes bust...........................
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'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go
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GDE's tune removes EGR. As far as oil clogging your inter cooler I'm not so sure it's a big problem. I've owned two VW tdi's and both would collect a little oil in the inter cooler. The 96 didn't have EGR and there was never a problem. The 99.5 had EGR and at 60k miles the intake manifold has half plugged with crusty black stuff and again at 120k.
It says MAX