Overheating at full speed

[Waterdog ls]

overheats at med seed and full speed.
I pulled the therm out and it was still running at 120.
The impeller was pulled out and it was in perfect shape no missing parts.

[mmandley]

overheats at med seed and full speed.
I pulled the therm out and it was still running at 120.
The impeller was pulled out and it was in perfect shape no missing parts.

I don't understand what you mean by pulled the therm out and it still was running at 120.

Ok well your running out of options.

You have the Impeller that pulls in water, water pump that circulates water, thermostat to hold warm temp, engine block, heads, and exhaust manifolds.

Other then that nothing else the water circulates through.

You can pull the thermostat to see if it over heats due to it being bad. Other wise there has to be a blockage in the block, heads, exhaust manifolds.

Just really isn't that much to the system.

[DOCDRS]

Ok , what does your temp gauge read when it is overheating. follow your intake line until you come to a cannister with 2hoses going to the transmission.......that is your tranny cooler. It may have weeds in it rducing flow unless you have a water strainer before it. If it runs at 120 without the thermostat that may be normal, i really dont know what it should be , but 120 seems reasonable. Maybe you need a new thermostat......you can test it in a pot on the stove with a meat thermometer.

[cornrickey]

When my 86 SN did this the reason was pieces of impeller was lodged in the discharge grate of the pump and pieces when in the hose between the pump and thermostat housing. I only found them after letting water drain from then and finding them in the bilge then found the larger pieces stuck in the pump housing. Good luck

[kaneboats]

Please look at post #1 in this thread and check yours to be sure:

https://forum.moomba.com/showthread....the-week-month

[Waterdog ls]

I believe I have the problem located.
It's a electrical issue. When I put the radio on or the bilge, basically any thing the thempature and the oil pressure will spike.
I believe that it is putting electoral resistance on the to meters.
Any ideas?
I'm thinking about rewiring the radio and other add-ons to be connected to the battery directly.