Dont see water circulateing when cap is off water hoses get stiff not sure if it is pump or thermastat?

(2011-06-19 14:20:05)

1. mrsbleary Says: doesnt overheat when moveing or a/c is off when idle overheats i noticed hoses very stiff made me think maybe thermastat sticking i took off cap and watched water when running it sat with no movement for awhile then started to boil over would there be movement of water by pump if thermastat is sticking or would a sticking thermastat make it look like no circulation at all

2. Pete M Says: Make sure that the engine is at normal operating temperature before assuming that the thermostat isn't working.

Thermostats rarely fail, and usually the worst that happens is that they get stuck closed.

Unless the car has been sitting for years, it's very unlikely that there is a problem with the thermostat

A sticking thermostat would not allow the water pump to prime and it wouldn't be able to circulate water through the block.

If the engine ran out of water, that could have destroyed the water pump too.

Another thing to check for is that the water hoses are hot. If they don't heat up and if the heater hoses don't heat up, it may be a bad water pump.