[Pupsvette76]

hey guys need help here... ive been chasing an oil leak for the last 3 days that seemed like a simple fix at first but i can fix it ...i noticed a lot of oil dripping down the back of my engine passenger side of the bell housing down near the starter... i traced it back to the passenger side valve cover so i replaced the warped stamped steel covers with tall aluminum moroso covers and used molded rubber mr.gasket cover gaskets ...took the car back out and still noticed a lot of smoke under the hood... i noticed the breather on boths side but mostly the passenger side spitting oil all over... so i figured maybe the breather is cloogged so i got a breather that looks like a little cone air filter with a shroud.. and still theres oil everywhere...so i put a pcv valve on the pass side and still its blowing oil out of the breathers...the oil pressure is very high at WOT approx 95psi... and it s a turbosmall block chevy motor at this point i think the crankcase is getting pressurized by some blow by and forcing oil out of the breather ...anybody have a good fix for this or know whats really going on

[vinniekq2]

do you have room for a vacuum pump? have you tried tall breather tubes as a quick fix and plum the gasses into the exhaust?

[Pupsvette76]

tall breather tubes? is that a item i can buy or do i need to make them

[sedanbob]

Do your new rocker covers have baffles under the breathers?

[vinniekq2]

you can buy them. look at any circle track car. running a line into the collector helps evacuate the fumes

[farmwalker]

Originally Posted by sedanbob

Do your new rocker covers have baffles under the breathers?

Yes! Check for baffles. I had this problem and tried changing alot of things but never fixed it. I never found out that my old valve covers didn't have baffles under the breathers till I got new valve covers. lol. But then I realized why I could never fix that leak from the breather. Hope this helps!

[Pupsvette76]

There are no baffles but I believe that there is a small leak near the corner of the cover ... Could it be due to high crankcase pressure? My oil pressure is high

[farmwalker]

Because there are no baffels, most likely the oil is shooting up into the crank case breather and is then dripping out of the filter. That is what was happening to me.

[Pupsvette76]

I've seen guys use vacuum pump to clear the crankcase they the breather ports on the valve covers but most of the time they are the very expensive mechanical pumps running off a pulley can an electric vacuum pump be setup to do the same thing

[MouseFink]

Pontiac engineers have always had trouble with oil blowing out the valve cover oil fill/breathers. In 1964, Pontiac engineers installed oil dripper-baffles under the valve covers and that eliminated 90% of the oil blowing out the oil fill/breather cap problem on the passenger cars. On the high performance vehicles, Pontiac first tried placing 3" stacks on the valve covers that contained a baffle and mounted a push-on breather cap and those were used on the high performance 1962-63 389/421 SD/HO engine. That design was continued in 1964 on the 389 GTO engines. The 1962-1964 389/421 SD/HO and 1964 GTO high performance engines did not use dripper-baffles under the valve covers because those engines either had solid lifters that required lash setting occasionally and some customers wanted to "lash-out" the pre-load on the hydraulic lifters on Sunday for an extra 500 RPM and the dripper-baffles would make that too difficult. The drippers were retained until 1979 but did not include any type of baffle. Those drippers were spot welded to the roof of the valve covers.

Finally the closed system was introduced in 1968 and the valve cover oil fill/twist-in breathers were eliminated. In 1968, one valve cover received a rubber plug and the other valve cover had a PCV valve located where the oil fill/breather cap was formerly located. That was the completely "closed" crankcase vapor return system.