pcv question
09-27-2009, 06:30 PM
#22
To the OP - FWIW, I have a revextreme catch can, and have it set up identical to Arrons post (#14). I go through a quart of 5w-30 every 1k miles. My can catches virtually nothing. At times there will be small amounts of a clear, petroleum smelling liquid, but never any oil.
09-27-2009, 07:17 PM
#25
To the OP - FWIW, I have a revextreme catch can, and have it set up identical to Arrons post (#14). I go through a quart of 5w-30 every 1k miles. My can catches virtually nothing. At times there will be small amounts of a clear, petroleum smelling liquid, but never any oil.
But even with low mileage motors in excellent shape I always see some caught between oil changes, even if it is only a tablespoon or so. Plese post detailed pictures of your complete setup with every connection so we can try and see whats up.
09-27-2009, 08:47 PM
#27
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From all I have talked to and read this is false. Unless you are running a gapless ring your motor will have blowby to some degree. That blowby has to escape somehwere and without a PCV draw from the intake it will exit the breather and is completely normal. I have learned ALOT about the function and purpose of the PCV systems from Aaron and T .Lewis and am currently working on my own setup.
09-27-2009, 09:30 PM
#28
From all I have talked to and read this is false. Unless you are running a gapless ring your motor will have blowby to some degree. That blowby has to escape somehwere and without a PCV draw from the intake it will exit the breather and is completely normal. I have learned ALOT about the function and purpose of the PCV systems from Aaron and T .Lewis and am currently working on my own setup.
.
09-27-2009, 09:43 PM
#31
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The port on the TB is the source of fresh air that is being pulled into the passenger valvecover. It is just a hole drilled "thru" the TB itself. The vaccume being drawn thru it originates from the intake drawing air out of the crankcase. You could plug that port on the TB and the valvecover and run a breather in the valvcover and accomplish the same goal. AT WOT there is lil to no vaccume but instead pressure built in the crankcase that needs to escape. It will take any path it can to get out somtimes back thru the passenger cover and out that TB port. Problem is sometime oil accompanies this and can wind up inside the TB/intake. The breather in the valvecover route eliminates this possibility.
09-27-2009, 09:49 PM
#32
The port on the TB is the source of fresh air that is being pulled into the passenger valvecover. It is just a hole drilled "thru" the TB itself. The vaccume being drawn thru it originates from the intake drawing air out of the crankcase. You could plug that port on the TB and the valvecover and run a breather in the valvcover and accomplish the same goal. AT WOT there is lil to no vaccume but instead pressure built in the crankcase that needs to escape. It will take any path it can to get out somtimes back thru the passenger cover and out that TB port. Problem is sometime oil accompanies this and can wind up inside the TB/intake. The breather in the valvecover route eliminates this possibility.
Yeah, and the breathers/filters are how my crankcase pressure can never build up at all. Yesterday I capped the valley cover port, I have a breather/filter on the drivers side valve cover and my vacuum from the intake sucks crankcase air from passenger side valve cover.
So the only way fresh air can enter my crankcase is through the drivers side valve cover and it can only escape through the passenger side valve cover......via vacuum going to the lower intake port.
.
09-27-2009, 10:06 PM
#33
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Do you have a catch can in the middle of th run between the passenger side valvecover and lower intake port? Thats where it should be and will be most effective. Also are you running a PCV valve if so where is it?
09-27-2009, 11:01 PM
#34
Simple as can be.
Vacuum being sucked from the lower intake port drawing crankcase gases out through the passenger side valve cover port.
Fresh air gets sucked into the drivers side valve cover port through a breather/filter.
PCV valve is right there near the intake vacuum port.
I have tightened the clamp down, on the PCV/valve vacuum line, to get the exact air flow I want from the vacuum suction. ((I think stock flow is way too much, unnecessary. So I cut it down to about 1/4 flow of normal))
The valley cover port DOES NOT have that breather/filter anymore, I capped it off.
This set-up brought my oil consumption to a HALT!!!!!!
09-28-2009, 12:02 AM
#35
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well after digging around im leaning toward sticking with the breathers on my valve covers. only guarranteed way to keep oil out. i can see myself spending 100something bucks on a catch can setup and paying for synthetic oil. when there is really no benefit.
the only remaining problem is risk of getting moisture in the engine. for some reason i get rust on my dipstick. the only way inside the motor is the throttle body and those breathers.
has anybody else had a problem with rust on the dipstick? i know condensation in an engine is normal.
the only remaining problem is risk of getting moisture in the engine. for some reason i get rust on my dipstick. the only way inside the motor is the throttle body and those breathers.
has anybody else had a problem with rust on the dipstick? i know condensation in an engine is normal.
09-28-2009, 09:20 AM
#36
The port on the TB is the source of fresh air that is being pulled into the passenger valvecover. It is just a hole drilled "thru" the TB itself. The vaccume being drawn thru it originates from the intake drawing air out of the crankcase. You could plug that port on the TB and the valvecover and run a breather in the valvcover and accomplish the same goal. AT WOT there is lil to no vaccume but instead pressure built in the crankcase that needs to escape. It will take any path it can to get out somtimes back thru the passenger cover and out that TB port. Problem is sometime oil accompanies this and can wind up inside the TB/intake. The breather in the valvecover route eliminates this possibility.
well after digging around im leaning toward sticking with the breathers on my valve covers. only guarranteed way to keep oil out. i can see myself spending 100something bucks on a catch can setup and paying for synthetic oil. when there is really no benefit.
the only remaining problem is risk of getting moisture in the engine. for some reason i get rust on my dipstick. the only way inside the motor is the throttle body and those breathers.
has anybody else had a problem with rust on the dipstick? i know condensation in an engine is normal.
the only remaining problem is risk of getting moisture in the engine. for some reason i get rust on my dipstick. the only way inside the motor is the throttle body and those breathers.
has anybody else had a problem with rust on the dipstick? i know condensation in an engine is normal.
With only breathers and no vacuum to pull fresh flushing air through, you will have to change oil every time you run to save the motor from long term damage. The rust you see in the dipstick is only a fraction of what is happening inside your motor. The moisture comes from the level of humidity in the air, and in FL there is a ton. But moisture is only 1 of the harmful substances that need to be evac'd out of the crankcase with the aid of vacuum. There is also unburnt fuel, sulferic acid, carbon particale, and other nasty stuff in the combustion gasses that slip past the rings (no motor has zero blow-by) and these are what cause the damage. Running a breather in each valve cover will release the excess crankcase pressure, but that is all it does. Without a cross flow of filtered fresh air through the entire crankcase those compunds accumulate in the crankcase, and every time the motor is run they "flash" off to vapor & mist.....but if not flushed out, when the motor is shut off and cools, they recondense inside the crankcase coating the internal parts with moisture & corrosion causing compounds and contaminate the oil reducing its ability to protect the internal parts. A simple oil analysis will show just what compounds are in the oil and what levels of each.
So yes, the breather will eliminate the oil in the intake usually, but at the expense of your engine over time.
LS6427 has it right, but w/out a proper oil seperating catchcan inline there will still be a small amount of oil being ingested into the intake....and any oil will cause some detonation and carbon build-up, but he has cured his excess oil usage.
09-28-2009, 10:01 AM
#37
At WOT the intake vent to the PCV system becomes a vaccum point, because at WOT ALL the air moving into the TB is pulled into the intake. Keep this in mind when designing a system.
09-28-2009, 10:41 AM
#38
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Here's pics of how mine is set up now.
Simple as can be.
Vacuum being sucked from the lower intake port drawing crankcase gases out through the passenger side valve cover port.
Fresh air gets sucked into the drivers side valve cover port through a breather/filter.
PCV valve is right there near the intake vacuum port.
I have tightened the clamp down, on the PCV/valve vacuum line, to get the exact air flow I want from the vacuum suction. ((I think stock flow is way too much, unnecessary. So I cut it down to about 1/4 flow of normal))
The valley cover port DOES NOT have that breather/filter anymore, I capped it off.
This set-up brought my oil consumption to a HALT!!!!!!
Simple as can be.
Vacuum being sucked from the lower intake port drawing crankcase gases out through the passenger side valve cover port.
Fresh air gets sucked into the drivers side valve cover port through a breather/filter.
PCV valve is right there near the intake vacuum port.
I have tightened the clamp down, on the PCV/valve vacuum line, to get the exact air flow I want from the vacuum suction. ((I think stock flow is way too much, unnecessary. So I cut it down to about 1/4 flow of normal))
The valley cover port DOES NOT have that breather/filter anymore, I capped it off.
This set-up brought my oil consumption to a HALT!!!!!!
the only difference i see in your setup and mine is youre supplying fresh air to the passenger side with adjusted flow. do you have any moisture problems like mine?
09-28-2009, 11:59 AM
#39
He won't have the moisture problems since he is evacing the crankcase from one side, and pulling filtered fresh air from the other. He is also metering, or controling the amount of vac pulled using a PCV valve so it is not pulling to much and drawing in oil that way.