Hissing from thermostat housing

[fil1983]

My 86' FJ60 has been over-heating. After it cooled down, I took a look and there was some water splatter in the engin bay (on the battery) and the plastic cap from the container on the oposite side of the radiator from the battery was "popped" off. I ran it again after it cooled down and then when it got hot, i turned the car off and could here hissing coming from the thermostat housing. There is also some crap coming out of the seem. Like gasket crap, I think. Anyway, How likely is it that the thermostat is stuck or could it be the water pump if there is hissing coming from the thermostat housing?

Broke so fingers crossed that I don't need a new water pump.

 

[inkpot]

Which seam has crap coming out? Water pump or thermo housing?

 

[2mbb]

how hot is it getting and under what conditions does it over heat?

I don't mean to be a pessimist, but what you describe sounds like you are generating really high pressures in your cooling, indicating to me that your head gasket is blown.

 

[inkpot]

how hot is it getting and under what conditions does it over heat?

I don't mean to be a pessimist, but what you describe sounds like you are generating really high pressures in your cooling, indicating to me that your head gasket is blown.

Could also indicate blockage in the cooling system, which could result in boiling over. John

 

[fil1983]

The truck will overheat if I just let it idle for a bit, say, ~10min. The hissing is coming from the thermostat housing. Also where the gunk is.

 

[FJ60Seth]

The radiator cap should be the first thing to vent. If steam is venting somewhere else it's defective.