1988 FourWinns with 4.3 Chevy mated to a Cobra outdrive.
New thermostat and impeller. Runs nice and cool (stays at 160 on muffs) but heats up under a load.
On the lake it quickly got up over 200 so I dropped back to neutral/idle. Thought it would cool back down quickly but it stayed hot. It did cool down if I keep the idle speed up around 1200 or so rather than the 800 or so normal idle.
Possible blockage in exhaust maqnifolds or other issues but I dont want to rule out the belt driven water pump on the motor. Water pump vanes possibly bad and not moving enough water to cool at low idle?
I know there are plenty of marine parts that can NOT be substituted substituted with automotive parts like a mechanical (vented) fuel pump, etc. Seems like a water pump is a water pump. Yes? No?
New thermostat and impeller. Runs nice and cool (stays at 160 on muffs) but heats up under a load.
On the lake it quickly got up over 200 so I dropped back to neutral/idle. Thought it would cool back down quickly but it stayed hot. It did cool down if I keep the idle speed up around 1200 or so rather than the 800 or so normal idle.
Possible blockage in exhaust maqnifolds or other issues but I dont want to rule out the belt driven water pump on the motor. Water pump vanes possibly bad and not moving enough water to cool at low idle?
I know there are plenty of marine parts that can NOT be substituted substituted with automotive parts like a mechanical (vented) fuel pump, etc. Seems like a water pump is a water pump. Yes? No?
