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Forgive me if I'm beating a dead horse again -
I'm trying to "clean-up" things on my 1972 C3 that are not "correct" or just in need of replacement.
I have the base 350/200hp engine w/ 4speed, no AC. My LEFT side valve cover has the PCV and Oil filler.
My RIGHT side has the breather tube leading to the flame arrestor in the dual snorkel air cleaner.
The car came to me with a push-in type breather in place of the oil filler cap.
Are there any positives or negatives in keeping the breather or replacing the original rubber oil filler cap?
As far as I know, a breather and PCV valve should not reside on the same valve cover.
Any input is appreciated.
Forgive me if I'm beating a dead horse again -
I'm trying to "clean-up" things on my 1972 C3 that are not "correct" or just in need of replacement.
I have the base 350/200hp engine w/ 4speed, no AC. My right side valve cover has the PCV and Oil filler.
My left side has the breather tube leading to the flame arrestor in the dual snorkel air cleaner.
The car came to me with a push-in type breather in place of the oil filler cap.
Is there any positives or negatives in keeping the breather or replacing the original rubber oil filler cap?
As far as I knew, a breather and PCV valve should not reside on the same valve cover.
Any input is appreciated.
You are correct. Sounds like the way it’s setup now your pcv will not be working properly. The breather or connection to the intake is a fresh air entrance for the pcv. The dirty pcv side goes to the carb. Most engines I have seen have the clean air and oil fil in the same cover. This is also normally on the passenger side.
On my '71 non-A/C 4 speed car (now a ZZ4 350 but I've kept it as stock looking as possible) the PVC is on the left valve cover and there is a hose running from the fuel vapor canister behind the left wheel well up the a "t" at the PVC then it runs to the front of the carb. On the right valve cover is the breather tube going to the bottom of the air cleaner where the flame arrester is.
Left side - You can see the PVC valve and the Vapor can hoses.
Right side - ridged curved pipe then a rubber tube going to the bottom of the air cleaner. Note the ZZ4 has the oil level dip stick on the passenger side.
Thanks guys, I thought it was incorrect. Now I'm wondering if the breather was placed for another purpose.
I've read elsewhere on the interwebs that replacing the cap with a breather will reduced crankcase vacuum, thereby relieving existing oil leaks.
I guess the reduction in pressure does not allow the oil to force itself through a faulty gasket.
The car is "fairly" oil leak free. Literally 1 or 2 drops parked in the same spot for 2 weeks.
There's only one way to tell. I'll replace the oil cap and see what happens.
11-18-2018, 08:55 PM
Oil filler cap or push-in breather
