Need a better PCV breather, I think.

[Old Yeller 1970]

I'm still working the kinks out of the engine in the sig. Today I finally realized what's been causing my oil leaks. With two 3/4" bottom vented Specter/Mr Gasket breathers installed one in each valve cover, oil starts to bubble out between the head and intake manifold once the RPM's get above idle. When I pull the breathers out, the oil stops leaking.

I'm guessing this means I need something a little more performance oriented. What kind of breather should I install that will work correctly?

[Wild83C10]

Those breathers should be sufficient. It sounds like crankcase pressure is coming from somewhere it shouldn't.
To have oil coming out between the head and intake sounds like a bigger problem. Have you pulled your plugs since this problem came up? Do you have the correct intake gasket installed. One that was recommended by the head manufacture or the intake man.?

[Old Yeller 1970]

I have Fel-Pro intake gaskets, I think they're the ones Edelbrock calls for. I've had the plugs out many times.

[cableguy0]

you need a pcv valve otherwise pressure will keep building. its normal to build crankcase pressure the pcv evacuates it. pcv in one side breather in the other

[Wild83C10]

It is normal to build crankcase pressure but to push oil out of the intake/head seal?


Have you retorqued your intake since you started the engine? The intake and exhaust manifold/headers bolts always need to be retorqued.

[clinebarger]

Did you put thread sealer on intake manifold bolts? without a PCV it whould push the oil past the threads faster.

[Old Yeller 1970]

Originally Posted by cableguy0

you need a pcv valve otherwise pressure will keep building. its normal to build crankcase pressure the pcv evacuates it. pcv in one side breather in the other

So how do I plumb it? Do I Tee it into the brake booster line?

Originally Posted by Wild83C10

Have you retorqued your intake since you started the engine?

Yes

Originally Posted by clinebarger

Did you put thread sealer on intake manifold bolts?

Yes

[clinebarger]

The PCV valve needs its own vacuum source, On my 70 (i also have a holley)
i have the PCV hooked to the carb, booster is hooked to the manifold (#8 intake port) heres some PCV info

Combustion engines produce varying amounts of blow-by gases--gases containing undesirable pollutants which seep past the piston rings and into the crankcase during combustion.

SYSTEM OPERATION
The PCV system prevents blow-by gasses from entering the atmosphere by routing blow-by gases into the intake manifold through a vacuum controlled ventilating valve and a hose while allowing proper crankcase ventilation.


Blow-by gases mix with the air/fuel mixture and are burned during combustion.
When the engine is running, fresh air is drawn into the crankcase through a tube or hose connected to the air cleaner housing.
When the engine is off , the spring holds the needle valve closed to stop vapors from entering the intake manifold.

When the engine is running, manifold vacuum unseats the needle valve--allowing crankcase vapors to enter the intake manifold.

In case of a backfire in the intake manifold , the valve closes--stopping the backflow and preventing ignition of fumes in the crankcase.

During certain engine conditions more blow-by gases are created than the ventilator valve can handle. The excess is returned through the air intake tube to the air cleaner and carburetor where it is burned in the engine.

[cableguy0]

never tee off the brake booster for anything. you will end up with brakes that dont work right. can you take any pictures of where its leaking from?

[Old Yeller 1970]

Originally Posted by clinebarger

i have the PCV hooked to the carb, booster is hooked to the manifold (#8 intake port) heres some PCV info

Yeah, I forgot about that tap into the manifold. Originally, I couldn't use it because it sat right under the carb, which was in the way. But I put on a 1" spacer that will give me the room to use it.

Originally Posted by cableguy0

never tee off the brake booster for anything. you will end up with brakes that dont work right. can you take any pictures of where its leaking from?

I bought a PCV valve and fitting to tap into the intake manifold. I'll install it sometime in the next week and report back on my findings.

[jgh64pkup]

mine was pouring oil out of the balancer seal and dipstick tube at about 5 grand
i changed breathers and it works great now
i hope you get yours figured out

[Old Yeller 1970]

Originally Posted by jgh64pkup

mine was pouring oil out of the balancer seal and dipstick tube at about 5 grand
i changed breathers and it works great now
i hope you get yours figured out

Mine starts doing it around 2-3K RPMs. Today would have been a beautiful day to get it fixed. Temps were in the mid 60's. But instead I worked on my wife's 38 Special getting the trigger set up for her and then tonight I went with my kid brother to see "Dances with Giant Smurfs" in 3D. If you don't mind the anti-capitalist, anti-military, Gaea-pantheistic-earth worshiping themes the visuals are well worth seeing on the big screen.

Maybe I'll get the PCV done tomorrow.

[jgh64pkup]

wheres crosby county

[Old Yeller 1970]

Hmmm, I just talked about "anti-capitalist, anti-military, Gaea-pantheistic-earth worshiping themes" in my 666th post. There's a little bit of irony in that.

[jgh64pkup]

yeah just a little bit
im scared for you now

[Old Yeller 1970]

Originally Posted by jgh64pkup

wheres crosby county

I ate supper at the Italian restaurant on the square in Eastland about two months ago on my way to Waco. Pretty good chow.

Crosby County is the next county east of Lubbock on Hwy 82. I live about 5 mi southeast of Ralls.

[Old Yeller 1970]

Originally Posted by jgh64pkup

yeah just a little bit
im scared for you now

[jgh64pkup]

was the resteraunt called salvatores

Originally Posted by Old Yeller 1970

[Old Yeller 1970]

Originally Posted by jgh64pkup

was the resteraunt called salvatores

Indeed it was.

[jgh64pkup]

Originally Posted by Old Yeller 1970

they have some good pizza
well if you come through again you should come by

[Old Yeller 1970]

Originally Posted by jgh64pkup

they have some good pizza
well if you come through again you should come by

Will do.

[Old Yeller 1970]

Hey all, I finally got the PCV valve installed today. And PRESTO, no oil leaks. I didn't get it done sooner because it's been pretty cold ever since the blizzard Christmas day. I still didn't take it out for a spin because our gravel driveway is still a muddy mess while all the snow drifts continue to melt off. I did let it idle for several minutes at 2-3k RPM's and am satisfied that this part of the puzzle is finished.

[cableguy0]

good deal knew the pcv would get ya fixed up