More ideas
Hi Scott,
Twice I've had problems like that. First time it was old impeller pieces that had been lodged in a benign place that moved to a smaller gap downstream and partially plugged the system. Delayed problems from a prior owner's negligence. In the other case I replaced my circulation pump (raw water cooled engine) with a more powerful pump thinking that would address my occasional overheating. Whenever I revved the engine the now stronger suction would close the hose upstream between the pump and the strainer by the through hull. The hose worked fine at low revs and with the less powerful pump. I replaces the heater hose that was there with suction rated hydraulic return hose and the problem was gone. The hose I used was from Parker - cheap, resists heat, oil, pressure and suction - and probably available off the shelf in your town from the local industrial hose/hydraulic supplier.
Paul
New Brunswick, Canada
Hi Scott,
Twice I've had problems like that. First time it was old impeller pieces that had been lodged in a benign place that moved to a smaller gap downstream and partially plugged the system. Delayed problems from a prior owner's negligence. In the other case I replaced my circulation pump (raw water cooled engine) with a more powerful pump thinking that would address my occasional overheating. Whenever I revved the engine the now stronger suction would close the hose upstream between the pump and the strainer by the through hull. The hose worked fine at low revs and with the less powerful pump. I replaces the heater hose that was there with suction rated hydraulic return hose and the problem was gone. The hose I used was from Parker - cheap, resists heat, oil, pressure and suction - and probably available off the shelf in your town from the local industrial hose/hydraulic supplier.
Paul
New Brunswick, Canada