Is crankcase breather interfering with engine performance?

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Hello.
I have a 1300cc engine (connected to a car of course...), and the crankcase breather was disconnected due to an oil leak that caused it to jam the carb.

Recently, I solved the oil problem, so I connected the breather back to the carb.

My question is whether the breather is actually helping the engine by burning more fumes, or is it interfering with the engine because it's choking the carb.?

posted by  malky

i'm assuming by "breather" you mean the PCV valve

well.... that depends on your idea of performance
if you want your engine oil to fill up with extremely caustic fumes, and your engine to last about 40-60K miles (maybe) then you should disconnect your PCV valve

a friend at another forum said it better than i could:


positive pressure in the crankcase can induce ring flutter and prevent sealing a vacuum in the crankcase stops that and also reduces windage from the crank and oil whipping

in short, re-install it

posted by  asa67_stang

thank you

posted by  malky

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