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Mon Apr 04, 2016 5:23 pm

Hello all!
I am new here and have a problem with a new dry sump. I built a 1914 3 years ago but kept the basically stock hi-flow oil pump. i decided to install a CB 4 gear dry sump this year as the motor is in a rail buggy and i was looking for better pressure and better cooling. i have 10 quart tank, 1/2" line to the pump, out from the pump to a remote filter then to an electric fan cooler, finally back to the tank. The problem, the pump doesnt scavenge the oil very well back to the tank, very sporatic! In fact, if i put 3 quarts in the tank and have about a quart in the engine, ALL the oil ends up in the engine within a minute! I split the case hoping to find a crack in the pick up tube or the tube not being seated well. The pickup is fine, put 20psi to it and plugged the hole in the case....no air leaking. Pat at CBPerformance was even stumped by this one! I expected a hi flow of oil leaving that pump, but its not. Help! ive ran out of ideas!

Mon Apr 04, 2016 10:19 pm

As you found out those pumps don't work the scavenge side needs to be least two times the size of the pressure side.

Look for a Auto-Craft or BugPack pump they have 6 gears.

Tue Apr 05, 2016 5:16 am

Are you still running a deep sump?
Assuming you've done nothing to modify the pump, how oil travels through its internal circuits, or how the oil system is routed, the pump is likely not in spec. Many people run the CB pump, and while it's not an optimal solution, it works. The scavenge stage is larger than the pressure stage, and especially when the sump fills full of oil it should out-scavenge the pressure stage. The fact that all oil ends up in the engine -which would be above the level of the oil pump (unless you're running a deep sump)- and the pump still isn't pumping more volume on the scavenge stage than pressure stage, suggests the pump is defective.

Tue Apr 05, 2016 2:31 pm

You're not talking about drain back to the engine are you? Is your tank a lot higher than the engine?

Tue Apr 05, 2016 5:11 pm

rrcade wrote: You're not talking about drain back to the engine are you? Is your tank a lot higher than the engine?

LOL...I didn't even consider what he described may be what's occurring when the engine is off :lol:

Tue Aug 23, 2016 5:31 am

Stripped66 wrote: rrcade wrote: You're not talking about drain back to the engine are you? Is your tank a lot higher than the engine?

LOL...I didn't even consider what he described may be what's occurring when the engine is off :lol:

Is this real? I have been a stock forever, but when I inherited a Beck Spyder it came with a 23xx cc CB Performance built monster breathing through IDAs and a 10 qt dry sump system. The car was built to spec by pros, but I have this same issue. It happens when the engine is off . . . Bad pump? Poorly sealed? Too much oil in the whole system?

Tue Aug 23, 2016 7:36 am

aircooledguy wrote: Stripped66 wrote: rrcade wrote: You're not talking about drain back to the engine are you? Is your tank a lot higher than the engine?

LOL...I didn't even consider what he described may be what's occurring when the engine is off :lol:

Is this real? I have been a stock forever, but when I inherited a Beck Spyder it came with a 23xx cc CB Performance built monster breathing through IDAs and a 10 qt dry sump system. The car was built to spec by pros, but I have this same issue. It happens when the engine is off . . . Bad pump? Poorly sealed? Too much oil in the whole system?

Yep. Gravity is a fickle b!tch.

Tue Aug 23, 2016 7:31 pm

just put in a shut off valve at the tank, then NEVER forget to turn it on before you start your engine