This step-by-step process is designed to prime a lake-fed, above-ground centrifugal or jet pump to ensure it has the necessary water pressure to draw from a lake or well. 

• Submerge the Foot Valve: Ensure the screened intake (foot valve) is submerged in the lake.

• Clear Debris: Clean off any silt, sand, or debris accumulated over the winter, which can block water flow.

• Check Integrity: Ensure the foot valve is securely attached and not damaged, as a faulty valve will lose prime. 

• Locate the Plug: Identify the priming plug on the top of the pump housing (the "wet end" or casing).

• Unscrew the Plug: Use a wrench to remove the square or hexagonal plug, turning it counter-clockwise. 

• Fill the Casing: Using a funnel or jug, pour clean water into the priming port.

• Fill the Intake Line: Continue filling until the water stays level with the top of the hole, ensuring both the pump casing and the entire intake line (down to the foot valve) are full.

• Tip: This can take several gallons of water, depending on the length of the intake pipe. 

• Replace the Plug: Reinstall the priming plug.

• Ensure Airtight Seal: Tighten the plug securely with a wrench, but do not overtighten, as this can crack the cast iron housing. Using Teflon tape on the threads can help prevent air leaks. 

• Open a Tap: Open a nearby cold-water tap, ideally an outdoor hose bib, to provide a release point for trapped air. 

• Start the Pump: Turn on the pump.

• Monitor Pressure: The pump should begin to operate. If it does not build pressure within 30–60 seconds, turn it off immediately to prevent damage to the seal. 

• Re-prime: If the pump fails to start, it often takes 2 or 3 tries to get all the air bubbles out of a long intake line.

• Troubleshooting: If the pump continues to fail, check the entire intake line for air leaks, which will prevent a vacuum from forming. 

Sources: Nightowl Monitoring, Ottawa Citizen, YouTube