A bad thermostat could be stuck open or stuck closed. Drop it in boiling water and it should open. Then close when cooled off.
Look where the upper radiator hose connects to the engine. There you will find the thermostat.
Look where the top radiator hose connects to the engine(water pump).
follow the upper radiator hose from the radiator toward the engine. the housing that the hose attaches to holds the thermostat. it should look like a little elbow housing held down by two bolts. it'll be part of the water pump.
spagettie
It has a Manual thermostat. The thermostat is normally located where the upper radiator hose connects to the engine. Look Carefully at this location.
The 1995 Chevy Conversion Van is a large vehicle with what some describe as an old school conversion van appearance. The 1995 Chevy Conversion Van gets about 13 miles to the gallon.
this model does not have a heater control valve, it has a specail thermostat that controls flow.
If you look at were the top radiator hose hooks to the top of the engine, you will see where it clamps onto a housing that has 2 bolts holding it to the engine.It is under that housing.
look at the top radiator hose, follow it to the engine and that metal thing is the thermostat housing, inside is the thermostat.
the head could be warped BUT try removing the thermostat because that could be a bad thermostat try running it without it if its a blown head will not have compression and the oil will look milky
Take a look where the lower radiator hose connects to the engine. Where the hose connects, you should find the thermostat.
Look in the removable housing at the engine end of the upper radiator hose