My motor blows oil and white smoke that has no smell thru the oil fill on the manifold. I have pcv hoses going from the valve covers to the big port on the bottom rear of the carb... to give you guys specifics on the motor its a 350 with a 750 holley carb that sits on top of a eddy performer manifold, with a real mild cam, no head work was done, and its got rams horn manifolds going to straight pipes. No other mods than other than I had a shop drill the manifold for the old style oil fill and the script v/c's ( I drilled holes for the pcv in the v/c's) When I drive "normal" it doesnt smoke ... but if I stand on it it gets worse and worse till it looks like im in the old arcade game spy hunter and I've got the smoke screen option!!!!! So any help on this anoying shit would help alot 'cause i cant figure it out !!!
I was thinking the same thing as Terry. If you drilled your own pcv hole did you add a baffel to stop the valve from sucking oil splash?
Pull the pcv valve out and run it if oil sprays everywhere you found your problem. Baffle that valve cover.
The "late" style (about 1968-and newer) factory sbc crankcase ventilation system uses an air intake on one valve cover, and a pcv valve on the other valve cover. air comes from the air filter thru the tube into the one valve cover, goes thru the valley and to the other valve cover where it gets sucked out the pcv valve into the intake manifold and burned by the engine. when the engine is making more blowby than the pcv can handle, the excess gets blown back thru the tube into the air filter, and ingested by the engine. I don't know how the setup you have on it is supposed to work....sounds like you need to just block off the vent in the filler tube, get rid of one pcv valve, and put a breather on the other valve cover (and baffle the pcv and breather holes in the valve covers, as the others said).
The problem isnt the motor "sucking up" any oil cause theres no smoke from the tail pipes...It blows directly out of the oil fill all over the out side of my motor.. the front of the engine and the carb are black from oil spraying outta the oil fill and the smoke comes from there too when it blows the oil out... I'll take pics tomorrow and post them on wednesday so you guys can see what im talking about Mike
Is the problem that actual oil is coming out of the fill and then smoking as it burns off the exhaust or is it smoke from the fill. Smoke from the fill would be more indicative of wear (blow-by). If it is the oil senario then I would look for a way to baffle that fill tube to keep the liquid in and let the vapor out. Try some baffled grommets as they stop the oil from soaking the baffle. And like Squirrel said one pcv valve is enough and a breather on the other side or on the filler tube. Another thought is how long is your fill tube? They were made to be long enough so that oil vapors would cool and condense and return into the engine. If yours is too short there isn't enough time for that to happen and then oil comes out (I have this problem on my bike and it is a mess, but it looks cool) Maybe you can baffle the tube?
the early engines that had the front intake mounted fill tube/vent also had a matching passage in the block, that connected it to the front cover area of the block, not the valley. So if it's a "late model" block the fill tube won't be working as designed. Also the early blocks had an external draft tube hole and passage at the back that connected to an oil vapor separator in the valley.
I did think about baffling the oil fill under the manifold but I thought there was a underlying problem with the way the motor was blowing the oil and smoking... So I thought it might be a waist of time to baffle the manifold if the motor was bad anyway... Mike
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