Check the inside of the hose between the valve and the carb.If it's oily,you've found your problem.If your car has the "restrictor' like Jeff mentioned remove it and replace it with a regular PCV valve unless you're heck bent on everything being of original design.
Blue smoke
- Thread starter Victorniner
- Start date
Good catch on the oil between the valve and the carb. That would resolve any of my concerns.
After re reading thru the previous posts,in one you indicated your oil fill tube is un baffled,in another Don recommended putting some coarse steel wool down into the tube below the PCV connection in the tube,did you try that?It is very important to have some kind of baffle where the vapor exits the engine.All factory systems have some sort of oil separator in line whether it be baffling, steel wool type mesh,or a dedicated oil separator.The coarse steel wool stuff was actually used by Ford in their FE HP intake manifolds and Lincoln MEL valley covers,there was a little basket packed full of the stuff that sat down into the otherwise unbaffled opening for the road draft and later PCV connections.I believe that the cannister that sticks into the valley of early small blocks for the road draft also was packed full of it.
That steel wool will let the engine breath but the oil mist will condense and flow back down into the engine is the reason for mentioning it in the first place.Now that the baffle is in place and that you have a good gasket seal,I'd try that next.
I believe he has the rear just going into the air filter housing, so that should be good. Maybe the wrong PCV, they do make different ones.
How much blowby does this engine have if you run it with the breather open and no PCV hooked up?
How much blowby does this engine have if you run it with the breather open and no PCV hooked up?
La is right on the money about pcv valves there are valves that look identical with different part numbers that have different vacuum setpoints and flow rates.The manufacturers could have different valves spec for different levels of tune for the same engine ie. 1 for an engine with 9 to 1 compression and hydraulic cam a different 1 for the same engine with 11 to 1 compression and solid lifter cam.
Victorniner
Well Known Member
well hmmm i have dual quad set up rear carb has vac being used for brakes so i ran to front but that does make sense maybe a longer hose ?
What duration cam are you using? Running lower brakes also ? You may not have enought vacuum for the pcv system to function properly. Just wondering since you have never mentioned your engine spec's.
Victorniner
Well Known Member
engine is a 62 qb with 690 heads crower cam previous owner didnt have cam spec,s its a little lumpy has had bigger valves installed and is a solid lifter cam what size steel wool? filler tube has no baffle. seems like you wouldnt want to get any of that steel wool down in lifter valley any chance of that?
I have my pcv valve in my filler tube, no baffle and it doesn't suck in any oil.
Victorniner
Well Known Member
I bought the bypass kit from how cars so maybe it is the wrong pcv valve
Victorniner
Well Known Member
No sir
Victorniner
Well Known Member
But with the amount of oil in there it's almost like its pulling it thru the valves
Did you try this?
What we are talking about isn't really steel wool its more like steel pot scrubbers if you google scrubble there's a restaurant supply company called acs keep following the links on there website and you'll see what I'm talking about but they're usually in grocery stores in the household items section,but its not Brillo pads,its much coarser.
Victorniner
Well Known Member
Ok thanks
How much vacuum at an idle speed of 700-750 rpm does the engine make? You can use the copper or brass colored pot scrubbers,only use about 1/4 of it .Shove it in to about 2 inches below the inlet for the pcv.WARNING;you'll now need to pour the engine oil in at a slower rate.