Picked up a janky shovelhead chopper this spring, built with a claw hammer and a blowtorch, ridden hard and put away wet.

I had the primary off for some repairs, and now that it's all back together I have a problem with oil puking out the inner primary when it's running. Hard to tell, but I think it's being pushed out of the hole for the fxe shifter arm.

The bike is running a wet chain primary, no chain oiler.

The three main oil lines from the oil tank to the oil pump are connected the way you'd expect:
Feed line from the tank going to the upper outer inlet on the pump
Return line from the oil tank going to the upper inner outlet on the pump.
Vent line from above the oil pump going to the oil tank.
Those are the only lines connected to the pump.


The vent line that is to the left of the oil pump on the case if you're looking at the motor from the back is connected to the inner primary.

That's it for oil lines and vent lines. No T connectors or anything else connected.

Should the vent line that is currently connected to the primary be vented to atmosphere? Or connected with a T to the oil tank/pump vent line?

Is it pumping out oil because of the way it's connected, or do I have a sumping problem? or both?

I can't see why it is connected the way that it is, but this is new territory to me.