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Crankcase Vent Lines

Shwine617

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Hi All,
I have a 1992 Honda CB750.
I removed the stock airbox and breather lines.
There is a vent fitting on the lower crankcase and one the valve cover.
Can I connect these two together or do they need to go to a vent/filter.
thanks for any input.
 
One end needs to be open. You should have a T connector left over. You can connect those two lines together and then run the third down behind the back of the engine. You might get an oil drip out of it once in a while so it should end low so it drips on the ground.

I assume you did this to use 4 single air filters. It may look cool but it causes a lot of issues. You can find many discussions on it in these forums. Good luck.
 
You MUST vent, if not the pressure buildup in the crankcase will then fail all your seal to start leaking all over the place.

Dave is right. Raise the line(s) up high at first to let oil in them drain back into motor, then let the remaining line length go down to the common dump point behind the motor. That way your oil use will stay low.
 
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