shower water pump rebooting

Shower water pump technician experienced expert needed please. To Stop/Cure a recycle kick in kick out re start from pump. It was about every 2/3 hours with no water running. Its now happening every 1/2 hour. I turned off the isolation values to pump and it got worse lol. Every 5 minutes and running on for even longer and more noisy. There are no pump leaks and its not getting hot. Its a Stuart Turner 4bar pump 5 years old. Terry.