QuestionAfter further investigation...the thermostat is working fine (boiling water test)...but i discovered the engine was short a gallon of water...
(i read it only holds 2)...but the radiator fluid reservoir was full.
So i'm losing water out of the engine...and its not drawing from the reservoir. I filled the engine with water, through the radiator cap, and ran it idle for about 5 minutes...with success...but the heater seems only slighty hot...does this sound like a blown head gasket? I'm a little scared to drive it.
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Followup To
Question -
Hello...
I have a 1984 toyota van, A/T, 137,000 miles...and all of a sudden its starting to run hot (radiator boils over...car temperature gauge is on H)...but my heater is blowing cold...
Answer -
For some reason there is no coolant circulation.
This could be caused by a number of things, the simplest is that the thermostat may be stuck closed, more serious reasons could be the radiator is clogged, the fan belt broke(there would be a battery light on the dash on),or a possible blown headgasket,or a bad water pump, change the thermostat first.
AnswerThere may be an external coolant leak, the best way to find this is by pressurizing the cooling system, most repair shops can do a test to determine if there is a headgasket leak.
A quick way to find out if there may be a headgasket problem is to remove the oil filler cap and looking inside, if there are light brown, milky deposits it means water is getting into the oil.
