Have Boat Questions? Ask a Boat Repair Expert.
Hello, my name is***** will assist you.
When was the last time the cooling system was serviced?
What about replacing the impeller?
Is the overheat light on the key switch panel the one that is coming on?
How long has the issue been going on?
When you shot the temps, did you do so at or near the temp sender on each cylinder head?
When you replaced the pump, did you ensure that the sealing o-ring was installed in the pump housing?
Inspect the harness going from the exhaust manifolds heading to the ECU. Make sure that there is no melted wiring or any parts of the loom.
200 wil trigger the alarm. Or it should. Have you tried to run the engine for a minute with the t-stat housings off and check the water flow to them?
With no water coming from either side, I would lean more toward the blockage being in the water tube or in the adapter plate. Lets start simple first. Remove the gear case again. Get a good strong flashlight and look up the water tube, Make sure that there is nothing blocking it. There is a ridge on the water tube that needs to be on the upper end, and not the lower. It is easy to get reversed if the tube has ever come out of the engine while doing a water pump.
When you look into the water tube, make sure that you cannot see any rubber from a grommet on the upper end.