I had a small leak on the pressure relief valve on top of hot water tank. Was enough to make the pump cycle a few times every once in a while.
Got one of those new pumps too. Best upgrade.
Those OEM pumps were a Rube Goldberg setup. And they are not cheap!!
-K
1986, 32' Sedan, twin 360ci, 275hp Chrysler's w/ K&N flame arrestors