oil in PCV?
Thread Starter
Team Owner
Joined: Feb 2001
Posts: 21,016
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From: Galveston... well, Santa Fe Texas
Cruise-In VII Veteran
St. Donor '03 & '06
oil in PCV?
my 84 is carb converted.
I'm using the stock magnesium valve covers with the baffles. I first noticed oil on the valve cover, centered around the grommet for the pcv valve.
I then pulled my vac hose and found trace amounts of oil on the inside of the hose, enough to notice it was there, but not enough to completely coat the screwdriver I used to check.
so my pcv must be pulling oil through... which would also explain the tiny bit of blue smoke i get at idle.
My PCV valve seems to operate normally... why am I getting oil?
since the EGR is gone, the PCV valve I'm using is off of a 77-or so vette, not the 84 style with the "T" fitting.
I'm using the stock magnesium valve covers with the baffles. I first noticed oil on the valve cover, centered around the grommet for the pcv valve.
I then pulled my vac hose and found trace amounts of oil on the inside of the hose, enough to notice it was there, but not enough to completely coat the screwdriver I used to check.
so my pcv must be pulling oil through... which would also explain the tiny bit of blue smoke i get at idle.
My PCV valve seems to operate normally... why am I getting oil?
since the EGR is gone, the PCV valve I'm using is off of a 77-or so vette, not the 84 style with the "T" fitting.
Race Director
Joined: Sep 2001
Posts: 14,679
Likes: 752
From: NEwhere Ohio
heres whats weird....
he could have totally normal compression & leakdown numbers and still be getting oil.
Heck the LSx series is well known for pushing oil and blowby into the intake via the PCV.
some oil blowby is totally normal.
Yes it stinks because it does coat the insides of your heads, pistons, and valves.
It can even eventually cause detonation as it forms carbon and increases compression.
I ended up plumbing an 'elite engineering' can inline with my PCV valve to catch oil and it does catch some oil.
I did this because I didnt want my pretty new AFR heads to get fouled up. Though I was told my old heads appeared 'normal' and not excessively oil fouled.
The next tear down will show if the elite engineering can kept everything clean.
However, if the OP is seeing oil on his spark plugs, there could be a problem beyond typical amounts of blowby.
I agree with the previous poster, do a leakdown / compression test.
Id also try to put back on original PCV parts too just for piece of mind.
he could have totally normal compression & leakdown numbers and still be getting oil.
Heck the LSx series is well known for pushing oil and blowby into the intake via the PCV.
some oil blowby is totally normal.
Yes it stinks because it does coat the insides of your heads, pistons, and valves.
It can even eventually cause detonation as it forms carbon and increases compression.
I ended up plumbing an 'elite engineering' can inline with my PCV valve to catch oil and it does catch some oil.
I did this because I didnt want my pretty new AFR heads to get fouled up. Though I was told my old heads appeared 'normal' and not excessively oil fouled.
The next tear down will show if the elite engineering can kept everything clean.
However, if the OP is seeing oil on his spark plugs, there could be a problem beyond typical amounts of blowby.
I agree with the previous poster, do a leakdown / compression test.
Id also try to put back on original PCV parts too just for piece of mind.
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
All pcv valves and hoses in all cars will contain oil. The pcv valve sucks up crankase vapors. The vapor is not pure, clean air. Instead is is a mix of combustion gasses and an oil film that floats around the inside of the motor. As this stuff is sucked up by vacuum into the pcv valve and hose, oil will be deposited inside the two. Motors with poor ring sealing will have more oil pulled out by the pcv. If you are smoking at idle, your rings or seals sound shot.
