Hydraulic Blunder

[nwtwa]

I recently repaired my control valve for my loader which was pretty straight forward. But in between the repair I decided to start the tractor up to look at the 3 point hitch only to realize I forgot to turn the control block valve that was feeding the loader and the PB to the 3 point position. Needless to say what a disaster . The main pump shaft, broke right where it connects to the engine. Good news is , that the engine connection is has little damage the bad news is I need a new pump. My question is, why would the main relief valve not have stopped this from happening?? I removed the valve, but could see nothing wrong with it.

 

[J_J]

Somewhere, you blocked the pump flow, or the relief did not relieve. Sometimes it will stall the engine.

If all hoses were connected correctly, valve in neutral and the switch was in the loader position, there should have been flow and no pressure from pump to tank.

Was a QD disconnected somewhere.

Can you not rebuild the pump with a new shaft?

 

[nwtwa]

Well it took the pump apart, short story, no the pump is gone. Looks like there was a little play in the pump, when the pressure built up the gears inside the pump dug into the pump casting seized the pump before pressure could activate main relief valve. at least that's what it looks like. I ll just have to remember if I disconnect the loader next time, is to turn the main control valve to bypass the loader feed and feed the 3 point hitch

 

[J_J]

You don't have to even turn the screw when you remove the loader.

Just plug the loader IN hose into the PB hose and cap the return hose.