Blow by and venting discussion.
11-06-2010 | 05:50 AM
#71
Joined: Sep 2002
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From: Sydney
11-06-2010 | 11:04 AM
#72
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Originally Posted by PWL,Nov 5 2010, 11:55 AM
I have bin trying to solve this problem for 2 years, on my F22C powered super seven.
I am running a dry sump, have the valve cover breather connected to a catch can, and the crank case breather is not connected (because of the crank case always being under vacuum). I finally tried to use a small electric oil pump, to pump the oil back from the catch tank to the oil tank, this works perfectly for me. It should work the same way on a wet sump engine, you could put a fitting in the sump or drain plug. I am using a pump similar to this:
oil pump
PWL
I am running a dry sump, have the valve cover breather connected to a catch can, and the crank case breather is not connected (because of the crank case always being under vacuum). I finally tried to use a small electric oil pump, to pump the oil back from the catch tank to the oil tank, this works perfectly for me. It should work the same way on a wet sump engine, you could put a fitting in the sump or drain plug. I am using a pump similar to this:
oil pump
PWL
Your setup should look something like this...
Obviously it's simplified for illustration purposes.
11-07-2010 | 04:24 AM
#74
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On dry sump systems, the scavenging action of the pump should evacuate any excess blow by gases in the crankcase. Ideally you would also have a Check Valve in the Breather Line to form a closed system. This allows the scavenge pump to run the crankcase pressure down to zero or possibly even a slight vacuum, but if a problem arises whereby crankcase pressure increases the valve opens to vent excess blow-by. A good catch can like Mocal for example have a VTA Cap, but on a dry sump system it is unnecessary.
11-07-2010 | 08:19 AM
#75
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The oilpump from the dry sump system is so strong / large that all blowby gases are evacuated from the crankcase?
That would make sense, and that's even good for power at higher engine speeds, because a small amount of vacuum helps the piston movement. They don't have to pump so much air inside the crankcase when going up and down.
That would make sense, and that's even good for power at higher engine speeds, because a small amount of vacuum helps the piston movement. They don't have to pump so much air inside the crankcase when going up and down.
11-09-2010 | 10:55 AM
#79
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this is how mine currently is setup i am considering drilling holes on top of the can so it vents to the atmosphere. its a spoon one and is internally baffled. does anyone see a problem if i were to drill say ten small holes on top of it?
11-09-2010 | 11:10 AM
#80
Joined: Dec 2007
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From: Savannah, GA, USA
Originally Posted by bpaspi,Nov 9 2010, 09:48 AM
F20C is longitudinal mounted, K20 transversal.