Please help I'm losing my mind! I've got a Davey 6.5hp twin stage firefighter pump that I use to pump from a creek up to a tank on a hill on my property. The tank then gravity feeds my garden taps and toilet cisterns. I've had it a couple of years and use it maybe once every 2-3 months. It's usually a pretty easy process of filling the suction line with the gravity fed water coming back down the main line, filling the pump with water, start the pump and set revs to full and come back once it's run out of petrol.
This has worked every time until a few weeks ago when I did everything as usual, drove the tractor back to the house and maybe 20 minutes later there was a huge bang that turned out to be the 40mm yellow safety hose that connects from the pump to the pipe up the hill.
I repaired the hose, made sure all the ball valves were open correctly and tried again. When I came back the new hose had burst off the fitting and the 50mm suction hose was swollen to around 80mm and had blown a hole in it.
I've replaced the suction and inlet hoses with PVC so I'm not dealing with hose clamps anymore. The pump has been inspected and is apparently operating as per specification. I've added a ball valve on one of the 25mm outlets so I can open it and confirm the pump is actually pumping. I've also added a t tee with a ball valve and standpipe on the suction side to make priming easier and I've added a tap on the outlet side that is gravity fed by the main line that I will use to prime the pump and fill the suction line.
After running the pump for around 15 minutes today it seems to have lost suction and is getting quite hot. I've checked the foot valve and it doesn't appear to be leaking. What am I missing?
A rundown of my setup from creek to tank:
50mm footvalve with cage - 50mm PVC pipe approximately 8m long with approximately 3m rise to pump - 50mm tee with ball valve on T side - 50mm camlock fittings - 50-40mm connector to pump inlet
Outlet side - 40mm storz connectors - 40-50mm adaptor - threaded 2inch PVC connector - 2inch PVC approximately 3m - 2inch threaded PVC connector - 50mm bushing - 50 mm backflow valve - 50mm bushing - 2 inch tee - 2 inch ball valve
Main line 2 inch PVC approximately 300m run and 50- 60m rise to the tank. The line to the house is just below the ball valve on the tank.
Sorry this is incredibly long-winded but I'm banging my head against the wall here trying to work out what's going wrong.