HELP PCV Valve Question

[oldstangs23]

So I installed a PCV valve/breather into the passenger side valve cover and hooked the vacuum up to the back of the carb - now I'm getting an oil leak near that area. The PCV valve/breather seems to fit snug into the rubber groument. Did I mess something up here? On the drivers side valve cover I have just a fitted oil cap, it looks similar to a radiator cap. Do I need a different style oil cap?

[PonyGirl]

baffled valve covers will fix ur leakage

[oldstangs23]

So that would eliminate the PCV valve?

[PonyGirl]

no..it will keep the oil from coming up and leaking

[oldstangs23]

So do you think it is leaking around the PCV valve itself? What if I just replace the rubber groumet in which the valve fits into?

[PonyGirl]

it wont fix it, had the same issue and tried everything. Bought some baffled covers and it fixed it. I think the pressure with the oil moving around just pushes it out through. the baffled covers will keep the oil from seeping through.

[oldstangs23]

What kind of price am I looking for these? I just don't understand why the original ones wouldn't/couldn't handle this.

[iamtheshaner]

You're almost always going to have positive crankcase pressure even with the vacuum on one side circulating air. Especially under throttle when the blowby is at max and there is simply no vacuum to scavenge the crankcase. Take that positive pressure, add it to the oil being flung around by your rockers and you get a big splashy mess of oil under the valvecover. This will eventually build up and saturate your breather. Baffled valvecovers are a must unless you are willing to frequently remove and clean this breather. It can be done either way, but one way requires a lot more babysitting than the other.

[PonyGirl]

i paid under 30 for mine, but new they will be more. just look around. Criagslist, Ebay.

[oldstangs23]

So I'm guessing that I will go with the your guys suggestion with the different covers. So if I'm imagining this correctly, there are baffles on the underside/inside of the covers to provoide some deflection of the oil?

[RegalX]

tie a rag around the breather....

[Max Power]

You should have a vented cap on the other side, not a radiator style cap. I thought we went through this last time you started a thread on it.

Don't waste your time worrying about baffled covers until you get a vented cap. If you still have the original cap, it should be large and vented. Use it.

A PCV system is a way of pulling air through your crankcase to vent your crankcase, directing it into your intake so whatever gases you vent will be burned off. Since the PCV Valve and tube going to the base of your carb could be considered the outlet of the crankcase, the cap on the other valve cover is the inlet. You won't have any airflow through the crankcase if you block the inlet with a non-vented cap.

Without your block being properly ventilated, blowby and pressure from gases within your engine will seek a way out through whatever outlet is easiest. Often, this is through the pcv valve area if you do not have a vented cap.

Your car and carb were designed properly with a functioning PCV system. Restore it to it's original condition. Judging from your threads here, you have very little working knowledge of this stuff. Don't modify things without knowing how they work.

Do a Google on PCV systems for a full explanation. The information is out there.

[oldstangs23]

The rag around the breather wouldn't look very nice but may ne a work around until I pick up some covers

[oldstangs23]

Max Power - I appreciate your input, really. But the style of oil cap I have on there is the same style I took off. Since what you posted makes sense, I will heed to your advise.

[Max Power]

Max Power - I appreciate your input, really. But the style of oil cap I have on there is the same style I took off. Since what you posted makes sense, I will heed to your advise.

It's always possible the previous owner installed the wrong cap. I bought my car out in Fresno and the guy didn't have a vented cap on there and the PCV blew right out of the valve cover while climbing the Tehachapi pass.

You can get a vented cover at any parts store. Or any Mustang shop like CJ Pony Parts.

You will need to know if you have the twist on style or push in style.

http://sitesearch.cjponyparts.com/search/Category-1964-1973_Engine_Valve_Covers_and_Breathers--keywords-oil_cap