[Rob Culver]

Hello all,
When I turn a faucet on in my TM to a low trickle the water pump will pulse, i.e. turn on and off about once per second. The water flow rate itself though does not pulse. As I turn the faucet knob increasing the flow rate it starts pulsing faster and faster. At about half the maximum flow rate it stops pulsing and the pump just stays on.

My question is: Is this normal? I cleaned out the filter and that didn't seem to change anything. The Shurflo 4008 manual for the pump suggests that one cause for pulsing (or rapid cycling as they call it), is that the shut off pressure valve is set to low.

Unfortunately, the location of this shut off pressure valve is very close to the underside of the sink and getting a 5/64ths allen wrench in to a very tight spot is quite difficult.

Has anyone succeeded in actually adjusting this valve or the bypass valve in order to eliminate pulsing?

Thanks in advance....