My 86 32v crankcase vent setup
#46
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Herman, nice schematics. Two questions:
Why no check valve in the return hose Provent to the MAF elbow - at idle it seems air will be sucked into the Provent from there
Why did you leave the driver side oil neck vent to TB in place - this route bypasses the Provent.
Why no check valve in the return hose Provent to the MAF elbow - at idle it seems air will be sucked into the Provent from there
Why did you leave the driver side oil neck vent to TB in place - this route bypasses the Provent.
#47
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The plastic “Y” fitting that goes to the passenger side of the rubber elbow has two different functions you can read about it in Mike Schmidt his write-up (attached)
The Provent has a build-in Pressure regulator (see schematic #2 # 4) only when the Bernoulli Effect starts at half to WOT will air be sucked out of the Provent where it has been separated from oil and oil vapors.
Porsche redesigned the GTS filler neck the vent hose outlet and moved it from the base to the top eliminated the check valve – this design is the same but routed via the Provent.
I left the driver side fill neck the same (it has a 2mm orifices inside) in order to sustain all the factory flow rates throughout the system
#50
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Well, 7000km later and I've just had the supercharger off to change the failed NEW water pump and the plenems are as clean and dry as I'd hoped.
Not the slightest trace oil, not even an oily film, the ProVent and system are working as planned.
Not the slightest trace oil, not even an oily film, the ProVent and system are working as planned.
So far I haven't seen any indication that the blow by is excessive. I did all this as the supercharger was being fitted as a part of the installation.
Of course it's early days and I've not seen inside yet, so I might get a nasty shock but so far the Provent seems to be doing its job.
I'm about to remove the supercharger to alter the way we have achieved the belt alignment and that will tell me if my boost breathing path is acceptable or the impellar is getting oiled.
Otherwise I'm pleased with it.
Of course it's early days and I've not seen inside yet, so I might get a nasty shock but so far the Provent seems to be doing its job.
I'm about to remove the supercharger to alter the way we have achieved the belt alignment and that will tell me if my boost breathing path is acceptable or the impellar is getting oiled.
Otherwise I'm pleased with it.
#52
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My opinion...
An oil separator will not cure oil blow by (from the piston rings) that exits via the exhaust. Over time I have heard/read from a lot of different owners how much variance there is based on their own findings with their specific cars related to the amount of oil consumption.
It's my believe that a lot of the different experiences in oil consumption are dependent on whether the original (first) owner of the vehicle strictly followed the factory guidelines on how to drive the car during the break-in period so the piston rings would get a chance to set properly seated versus stepping on it from day one.(very tempting to show off your new car).
It would have been nice to have been the fly on the wall when the discussion at Porsche where going on which made them lean towards the decision to no longer have oil drain back holes in the pistons of the GTS model as a trade of for cylinder wall/piston wear longevity.
Q; Is there still somebody at Porsche (or was part of that team at the time)that can really tell us other than any of the armchair quarter backs on this subject that you can find anywhere
#54
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Herman,
Well, I'm well pleased with the oil consumption as it's WELL below Porsche specs in the owners book.
Given I run Mobil One 0W40 full synthetic and have done for some years and it's now at about 193,000km.
Well, I'm well pleased with the oil consumption as it's WELL below Porsche specs in the owners book.
Given I run Mobil One 0W40 full synthetic and have done for some years and it's now at about 193,000km.
Excellent - The installation of an oil separator goals are keeping the intake plenums oil free and this is what your main objective is to get the right air/gas mixture to enter the combustion chamber.
An oil separator will not cure oil blow by (from the piston rings) that exits via the exhaust. Over time I have heard/read from a lot of different owners how much variance there is based on their own findings with their specific cars related to the amount of oil consumption.
It's my believe that a lot of the different experiences in oil consumption are dependent on whether the original (first) owner of the vehicle strictly followed the factory guidelines on how to drive the car during the break-in period so the piston rings would get a chance to set properly seated versus stepping on it from day one.(very tempting to show off your new car).
It would have been nice to have been the fly on the wall when the discussion at Porsche where going on which made them lean towards the decision to no longer have oil drain back holes in the pistons of the GTS model as a trade of for cylinder wall/piston wear longevity.
Q; Is there still somebody at Porsche (or was part of that team at the time)that can really tell us other than any of the armchair quarter backs on this subject that you can find anywhere
An oil separator will not cure oil blow by (from the piston rings) that exits via the exhaust. Over time I have heard/read from a lot of different owners how much variance there is based on their own findings with their specific cars related to the amount of oil consumption.
It's my believe that a lot of the different experiences in oil consumption are dependent on whether the original (first) owner of the vehicle strictly followed the factory guidelines on how to drive the car during the break-in period so the piston rings would get a chance to set properly seated versus stepping on it from day one.(very tempting to show off your new car).
It would have been nice to have been the fly on the wall when the discussion at Porsche where going on which made them lean towards the decision to no longer have oil drain back holes in the pistons of the GTS model as a trade of for cylinder wall/piston wear longevity.
Q; Is there still somebody at Porsche (or was part of that team at the time)that can really tell us other than any of the armchair quarter backs on this subject that you can find anywhere
#55
Nordschleife Master
The plastic “Y” fitting that goes to the passenger side of the rubber elbow has two different functions you can read about it in Mike Schmidt his write-up (attached)
The Provent has a build-in Pressure regulator (see schematic #2 # 4) only when the Bernoulli Effect starts at half to WOT will air be sucked out of the Provent where it has been separated from oil and oil vapors.
Porsche redesigned the GTS filler neck the vent hose outlet and moved it from the base to the top eliminated the check valve – this design is the same but routed via the Provent.
I left the driver side fill neck the same (it has a 2mm orifices inside) in order to sustain all the factory flow rates throughout the system
The Provent has a build-in Pressure regulator (see schematic #2 # 4) only when the Bernoulli Effect starts at half to WOT will air be sucked out of the Provent where it has been separated from oil and oil vapors.
Porsche redesigned the GTS filler neck the vent hose outlet and moved it from the base to the top eliminated the check valve – this design is the same but routed via the Provent.
I left the driver side fill neck the same (it has a 2mm orifices inside) in order to sustain all the factory flow rates throughout the system
Where is this check valve? I have two y-fittings and neither has a check valve. The hose is a straight hose and neither the plastic nor the metal filler neck I have have any check valves. Are my engines missing something, did they change the design, or what? Everything I have at hand is from 1987.
Mystery solved, my spare 87 engine has a check valve.
Looks like I've lucked into two oil filler necks with the check valve missing. Photos show that other people have check valves galore. Wonder if someone pulled them off or whether they came like that from the factory? What's the part number?
Last edited by ptuomov; 04-05-2014 at 01:57 PM.
#56
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Where is this check valve? I have two y-fittings and neither has a check valve. The hose is a straight hose and neither the plastic nor the metal filler neck I have have any check valves. Are my engines missing something, did they change the design, or what? Everything I have at hand is from 1987.
Mystery solved, my spare 87 engine has a check valve.
Looks like I've lucked into two oil filler necks with the check valve missing. Photos show that other people have check valves galore. Wonder if someone pulled them off or whether they came like that from the factory? What's the part number?
Mystery solved, my spare 87 engine has a check valve.
Looks like I've lucked into two oil filler necks with the check valve missing. Photos show that other people have check valves galore. Wonder if someone pulled them off or whether they came like that from the factory? What's the part number?
#58
Nordschleife Master
I don't think that anyone in the aftermarket performance parts business would come up with the sexy name of "de-icer valve" (WSM 24 - 218). ;-)
Photo courtesy of Dwayne:
Photo courtesy of Dwayne:
#59
Electron Wrangler
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I think Herman just meant his check valve in his HKR3 system (to rear pass cam cover elbow) is an aftermarket valve - presumably he would never have had a Porsche check valve on his GTS...
This just slides inside to metal port and both seal to the hose..? Does someone have a de-icer valve to hand that can test the cracking pressure?
Why on earth do they call it a de-icer valve (meshes with the patent wording) but how is this a major concern? the primary path ices up where exactly - at the elbow restrictor? (and why would it?)
What would also be really interesting to go with this is if somone could just test what the gauge vacuum is on that check valve port at various cruise rpms (say 2K, 3K, 4K)... also be interesting to know the gauge vacuum at the other port on the Y to the valve cover - since this differential is actually what will drive most flushing flow. Tricky to do on an S4 - but easier on a GTS (even though no valve) - just pull that line and cap the port & put a vacuum gauge just on that line - for the other into the Y do essentially the same, I think one breather should be enough at up to 4K.
I'd do it - only my Y is no longer there nor any plumbing to it... just a bung.
Alan
This just slides inside to metal port and both seal to the hose..? Does someone have a de-icer valve to hand that can test the cracking pressure?
Why on earth do they call it a de-icer valve (meshes with the patent wording) but how is this a major concern? the primary path ices up where exactly - at the elbow restrictor? (and why would it?)
What would also be really interesting to go with this is if somone could just test what the gauge vacuum is on that check valve port at various cruise rpms (say 2K, 3K, 4K)... also be interesting to know the gauge vacuum at the other port on the Y to the valve cover - since this differential is actually what will drive most flushing flow. Tricky to do on an S4 - but easier on a GTS (even though no valve) - just pull that line and cap the port & put a vacuum gauge just on that line - for the other into the Y do essentially the same, I think one breather should be enough at up to 4K.
I'd do it - only my Y is no longer there nor any plumbing to it... just a bung.
Alan
Last edited by Alan; 04-06-2014 at 08:12 PM.
#60
Developer
I was excited when the ProVent came out and we tested it right away. It was a fail for us, the screen inside was too fine, and as the crankcase pressurized they would overflow. I also remember when the plastic cover for the Pro-Vent would get warm it was soft and the crankcase pressure would blow it off. There is a thread or two about mine and others experience with the ProVent.
I've looked at your diagrams and I cannot make out which way those "one-way valves" are pointed. I assume they are installed so that (hopefully) the oil separated by the Pro-Vent can only flow TO the oil pan, and oil from the pan cannot be pushed up. But what will happen is that the crankcase pressure will hold that valve shut, the oil from the separator will accumulate in the hose because it cannot drain, until it either burps out or into the intake.
Is that what you are having happen?
I've looked at your diagrams and I cannot make out which way those "one-way valves" are pointed. I assume they are installed so that (hopefully) the oil separated by the Pro-Vent can only flow TO the oil pan, and oil from the pan cannot be pushed up. But what will happen is that the crankcase pressure will hold that valve shut, the oil from the separator will accumulate in the hose because it cannot drain, until it either burps out or into the intake.
Is that what you are having happen?