piper184
Gold Member
The pump is probably a fixed gear type. It displaces the same amount of fluid every revolution (minus internal leakage) so faster rpm means more fluid per unit of time.
You are correct, the pump can only produce pressure if it has something to push against. Normally that is the function of the relief valve. It keeps the end of the hose pinched off until it hits the limit then opens a little to let off some pressure.
It would be interesting to see what the pressure is between the priority valve and the 3 point valve where the main relief valve is located.
Also interesting would be what the pressure at the pump hose is when the loader is out of the circuit and the flow goes to the priority valve first in line.
To my mind they should all be the same 200 psi, but I might be missing something here.
Anyway, glad it is working. You now have more experience and some useful tools for future needs.
You are correct, the pump can only produce pressure if it has something to push against. Normally that is the function of the relief valve. It keeps the end of the hose pinched off until it hits the limit then opens a little to let off some pressure.
It would be interesting to see what the pressure is between the priority valve and the 3 point valve where the main relief valve is located.
Also interesting would be what the pressure at the pump hose is when the loader is out of the circuit and the flow goes to the priority valve first in line.
To my mind they should all be the same 200 psi, but I might be missing something here.
Anyway, glad it is working. You now have more experience and some useful tools for future needs.