All Small Six Crankcase ventilation on 66 200ci
- Thread starter Fred C
- Start date
This relates to all small sixes
aussie7mains
Famous Member
No such thing as totally closed, the crankcase needs ventilation. So its either a PCV system or a road draft tube. For 66, most cars (here in Australia) still had a road draft system with a tube from the block. From 69 we have a PCV system to reduce hydrocarbon emissions, I would imagine the USA is not much different. If your block has the road draft hole in the front you can plug this and run a PCV system which is better in my view. If your going for originality you can run the road draft tube and put up with the fumes. The blow by should be minimal for a new engine such as yours. IMO I would go with the PCV setup.
Fred C
Well-known member
The car does have a PCV system. I think my air cleaner is for a California 66 200ci because it has a side snorkel and a small tube that would connect by a hose to a tube on the oil cap. Since I live in Georgia, USA not California would there be any problems if I used this set up on my engine. Or would it be better to use a air cleaner without the tube and a oil cap without the tube as well. This is all new to me and I just don't want to have any issues.
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Hi, you want the PVC valve to be hooked up to a large 3/8 hose to direct vacuum, all by itself. Early engines use an oil filler cap with mesh inside. This allows engine compartment air to enter the valve cover. There are also aftermarket oil filler caps which work well. Later engines use an arrangement with a tube to the air filter housing so the air that enters the valve cover is filtered. Make sure the valve cover has some sort of baffle inside. Good luck
The California closed crankcase ventilation system is the way to go.
Connect a closed system oil breather cap with a 5/8" fitting to the 5/8" fitting on the air cleaner snorkel.
Use a piece of 5/8" heater hose.
Fresh air can enter the snorkel then make it's way to the crankcase by PCV valve suction .
Any excess blow by will be routed from the closed breather cap to the air cleaner snorkel to be burned in the combustion process.
I was issued a California Smog license before I got my first auto mechanic job. This was around 50 years ago.
Connect a closed system oil breather cap with a 5/8" fitting to the 5/8" fitting on the air cleaner snorkel.
Use a piece of 5/8" heater hose.
Fresh air can enter the snorkel then make it's way to the crankcase by PCV valve suction .
Any excess blow by will be routed from the closed breather cap to the air cleaner snorkel to be burned in the combustion process.
I was issued a California Smog license before I got my first auto mechanic job. This was around 50 years ago.
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