Oil tank draining down

Is the Oil tank draining down a normal thing on these Knuckleheads? will it lose prime on the pump when all the oil is in the crank case? this happens in about a week of setting
EL Roccky

Virtually all of them will sump at some point, but a week is on the extreme end. Many will do it if left unridden for a long period, most ridden regularly do not do it at all! So it is not normal. Sounds like time to check the seats in the pump and replace the check balls.
Robbie

I just had this motor put together by a shop that specializes in Knuckleheads, and they had to replace one gear in the pump, Maybe they did not do everything they shoud have to the pump, this motor had been sitting almost 60 years.
Thanks EL Rocky

And while you are inspecting the check ball and seat, don't forget the check ball spring. There is always a possibility that it is over 70 years old and has lost much of its tension.

Thanks guys, should the spring be stretched a bit to give more tension? and yes this is the original 1936 spring, this motor even had standard .250" rollers in the mains and crank pin
Rocky

[Pa]

I would not suggest stretching the spring in order to gain tension. It will only collaspe again because spring tension is tempered in when the spring is freshly manufactured. Most spring steel is manufactured in long length and then cut to standard lengths per application.

10-4, I will just get new manufactured springs, kinda like valve springs, old is old
Thanks
Rocky