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Correct Valve Cover breathers

I have a older carb chevy V/8, I understand there is a closed loop system and a open system when it comes to what valve covers to use. I currently have the valve covers {Edelbrock}that have the large Breather/Filler that vents to the air cleaner and also a PCV Valve. I seem to be using a large amount of oil with this approx. 1980 something

350CI rebuilt motor. I see no oil burning out the tailpipe, even though it is black, but plugs are burning clean and no oil at start up, or going down a hill, or when I open up the breather cap. But 180 miles to a liter/Quart and the motor now has 4000 miles since being rebuilt. Do I have the correct system for valve covers, I see that Summit lists to types for chevy V/8's. The orginal 305 as I remember has a PCV Valve and filter cap that was not a breather.
Reply to
cabopeter
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If you are losing a quart of oil evey 180 miles then I'd get under the car and see where it is going because at that rate you'd be fouling plugs once a week. More likely the rear main seal is leaking and you haven't seen it yet. Do you know how much oil pressure your engine is producing at different rpm ranges?

...Ron

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68' Camaro RS 88' Firebird Formula 00' Mustang GT Vert
Reply to
RSCamaro

Not leaking any oil,not fouling plugs,they are burning clean.Oil pressure is fine. Tail pipe is black but plugs are whitish grey

Reply to
cabopeter

You do understand that a quart every 180 miles is the same as 3 hrs of run time at 60 mph. Your tailpipe wouldn't just be sooty, it would have grease coming out of it. You are losing oil elsewhere. That high of an oil consumption would leave a trail of blue smoke everytime you put a load on the engine.

...Ron

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68' Camaro RS 88' Firebird Formula 00' Mustang GT Vert
Reply to
RSCamaro

OK, you're not leaking it. You're not burning it. Have you tried parking in a more secure location?

Reply to
Al Bundy

Thank you the Bright answer so lets explain again. I have driven this car with the rebuilt engine in it for almost 3,000 miles. It uses the amount of oil I stated. And for the smart guy, no one has stolen the oil. So lets get back to the original question, is this breather system correct. I don't see any other way on the older S/B Chevy's. PCV vents into the Carb base and the filler/breather vents into the base of the air cleaner. It has to be burning oil out of the exhaust but it can not be seen under load or going down hill.

Reply to
cabopeter

Is your air filter filled with oil when you inspect it?

...Ron

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68' Camaro RS 88' Firebird Formula 00' Mustang GT Vert
Reply to
RSCamaro

wrote: (older S/B Chevy)

I have driven the rebuilt engine almost 3,000 miles. It uses the amount of oil I stated. Is this breather system correct: the PCV vents into the Carb base and the filler/breather vents into the base of the air cleaner. It has to be burning oil out of the exhaust but it can not be seen under load or going downhill. ____________________________________________________

Yes, that is the correct PCV/Breather arrangement.

When you find the reason for the unusual oil consumption, will you please post it here.

Good luck.

Rodan. _____________________________________________

Reply to
Rodan

Thanks, I have checked the inside of the aftermarket aircleaner and is dry, not a sign of oil. Even if I open the breather while its running there is no blow by. Not the solution but a may which from 10-30 to

10-40 or 20-50 now that it has 3000 miles on it. Few of my mechanic friends say don't worry until you have 6000 or 7000 miles on it. The motor itself runs great, no problems at all under full load. Thank-you
Reply to
cabopeter

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