|
PCV has been required in the US since 1963. Before that the blow by from combustion was vented into the atmosphere through a tube. You could see the cloud of noxious fumes blowing out from under the vehicle.
By creating a slight vacuum in the crankcase PCV actually reduces oil consumption somewhat. A plugged PCV allows crankcase pressures to become elevated, which would actually make oil consumption worse. We used to buy cars with plugged PCV valves, in the 1960S. when I was a teen. A 63 Valient would burn a quart of oil in 400 miles, with 40k on the odometer. After cleaning the PCV consumption would drop to 1 quart in 1500-200 miles. These were engines that were caked with sludge internally and had not been well maintained.
The slight vacuum in the crankcase with a properly functioning PCV would help very slightly with pumping losses inside the crankcase.
If your PCV is plugged, your oil consumption would be significant.
The substance you are seeing in your PCV system, does not sound normal (just my opinion). It may be the beginning of a head gasket problem or something else that is allowing condensation or coolant into the bottom end of your engine.
It could also be due to very short trips without sufficient warm up time, for the condensation to be heated enough to vaporize and flow out through the PCV system.
Carefully monitor your coolant level for slight losses. Try to drive at least 50 miles occasionally, especially in very cold weather, or at least combine trips to the point where the oil in your filter gets too hot to hold your hand on the filter.
If necessary restrict flow to the radiator to enhance warm up. Make sure you have a properly functioning thermostat. Hold your had on the top hose and you can feel the dramatic change in temp when the thermostat opens. If not it is probably not working properly.
regards
Mech
|