Don"t touch that bolt

[Dick Steinkamp]

Originally Posted by J Franklin

Thirty wt oil in the early morning is quite viscous The pump tries to pump lots of oil and sometimes needs a relief. the oil spills back into the pan. This is why most oil pumps incorporate a spring loaded relief valve. Something would have to already be seriously wrong to press hard enough to uncouple the pump.

It looks to me like the oil is pumped to the rectangular slot near the top of the shaft then travels up to the valve chamber via the groove in the shaft. The pump would still have to pump oil the same distance dropped or not dropped. I don't see how this would be a "relief" for the pump. If it does drop, how does the oil travel back to the pan? It doesn't look like there is a path to do so.

I'm sure there is an explanation, I just can't see it yet.