I have a 1987 centurion Tru Trak II with a PCM 351. The boat is having overheating issues and the following parts have been changed.
1. Raw water pump impeller
2. Engine circulating water pump
3. The exhaust manifolds and the the uppers
4. Thermostat
The question I have is on the lower thermostat housing. I was inspecting it and I noticed an edge inside that I believe is a hole in the housing that seems to allow the fresh water inlet and the water exiting under the thermostat to mix. I see the hole in the upper housing that provides water to the manifolds prior to the thermostat opening. Should this passage way exist or is this corrosion that has eaten through the housing?
1. Raw water pump impeller
2. Engine circulating water pump
3. The exhaust manifolds and the the uppers
4. Thermostat
The question I have is on the lower thermostat housing. I was inspecting it and I noticed an edge inside that I believe is a hole in the housing that seems to allow the fresh water inlet and the water exiting under the thermostat to mix. I see the hole in the upper housing that provides water to the manifolds prior to the thermostat opening. Should this passage way exist or is this corrosion that has eaten through the housing?