I have a Mc Donald shallow water 8611 pump with the square D pumptrol and the pump motor will not shut off. The right pair of contacts in the switch show considerable wear. The switch is a 30-50 and gauge is reading 30. Is the problem likely to be the switch, tube or is there a clean out in the pump head that could be clogged?

You could have a number of problems including a new switch. See if you can measure the pressure in your pressure tank using a basic tire gauge on the air inlet (where you put air in to pressurize your tank). If the bladder in your tank is leaking, your pump will continue to try to build up pressure. Remember, if you have to replace the switch, you need to shut off the water supply and relieve the pressure by opening up a faucet. Hope this helps.

You have a 30/50 switch. Your gauge is showing 30# of pressure. Sure sounds like your pump is not getting up to cut out pressure. How many pipes go into your well, one or two?

It would be wise to check your tank. There is an air valve at the top. Depress the valve center for a few seconds. Should get air, not water. If you get water, then the tank is bad.

Thanks for the tips. I have verified tank bladder pressure at 25 lbs, and have checked to verify that nozzle/jet opening is not clogged in pump head. I have new switch on the way and the contacts on the current one look pretty worn down. I'll let you know if pump switch is the fix. Correct pump number is 8111 (not 8611) and is it likely the venturi or nozzle need replacing? I should also add that this is a booster pump for low city water pressure and it is mounted at same level as incoming water supply.