WM75Guy
Elite Member
The basics:I do know how to operate the PTO to engage pumps. Engage in neutral, once light comes on, shift Allison transmission to drive (but never do until I have valves open)
So lets start with the basics. How to fill.
Here are all my controls and valves.
Talk to me in dummy terms, LOL
How would I fill it?
I see most everything is numbered.
The tank should have a fill tower in the hose bed. Pop open the cover and drop in a garden hose to fill the tank. You know it is full when it overflows.
1. Open Tank to Pump
2. Open Tank Fill. Switch into pump gear as your described
3. Raise RPMs up to increase pressure using Vernier throttle. It should twist to lock in place.
4. The 2 large gauges showing incoming pressure (or vacuum if drafting from a water source) and pump pressure. If using tank water one of them will be on 0 PSI and the other showing pump pressure.
If you have a hose connected to a discharge just open and close that valve slowly to charge the hose. Pressure will show on the gauge corresponding to that discharge.
The lower connections are for water into the pump from an external source such as a hydrant. The large 6'" opening with the cap is for either a butterfly valve or Storz valve to connect to a hydrant or supply line from another engine. Just keep it capped. The smaller ones with female swivel connections and cap plugs are for 2 1/2" hose to supply water to the pump. Drafting from a pond or portable tank requires hard suction hose. Water under pressure coming in uses soft hose.
The priming pump is used to draw a vacuum in the pump when drafting from a pond or portable tank. It should have a small oil tank behind the pump panel or on top of it. You shouldn't need it for normal operations, the tank should fill the pump so it draws water in without the need for priming. If needed, just bump the primer for a few seconds till the large gauge shows pressure.
The large handwheel on the top right labeled Relief Valve is a safety device. It allows you to set a pressure that the pump will not exceed. A centrifugal fire pump takes advantage of the pressure coming in. If the pressure on the supply line is 50 PSi and the pump is putting out 100 PSI, the discharge pressure will be 150 PSI. If the supply line pressure increases, it passes through to the discharge pressure. You set the pressure using the Vernier throttle so the handlines have the required nozzle pressure. Then you set the relief pressure slightly above that by rotating the wheel counterclockwise till the pressure drops, then slowly clockwise till you get your pressure back. I would then give it a little more clockwise rotation, say a quarter turn. That way if you get a sudden surge of pressure coming in, it doesn't transfer through to the hose lines throwing folks around. It dumps out the bottom of the,pump. If you are just checking the pump just screw it clockwise till it stops, that way you don't have to worry about it.
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