To replace the thermostat in most vehicles yourself;
Remove the hose from the housing, then remove bolts from the housing and lift the housing off
to access the thermostat. Pay attention to witch side is up on the thermostat that you remove, the
new one will have to go in the same way. Also look at the temperature rating that is stamped into
the thermostat that you take out, and make sure the new one has the same temperature rating.
(failure to do so can cause false readings by some sensors, and may start triggering error codes)
Install new thermostat, right side up, put housing back on and bolt back down, hook hose back on
to the housing. Check the coolant level. Start the engine and let it run for 6 to 8 minutes to reach,
"normal operating temperature", and look for any leaking. before you turn the engine off turn you
heater wide open and listen for a click. Most of the time when a thermostat opens you can hear a
click and may hear the coolant flowing through the system. Shut the engine off, wait for it to cool
down and then check your coolant level one more time. ( do not fill all the way up, only fill to
FULL line on resrvior.)
If you want to double check the thermostat first;
How to test the thermostat in most vehicles;
Make sure the heater is off, start the engine and let it run for 6 to 8 minutes, ( this will allow the
engine to reach, " normal operating temperature "), from the inside of the vehicle turn the heater
temperature on high and turn the fan speed on high.
1. Listen very closely for a click sound from the engine, ( most thermostats make a click when
they open )
2. Watch your temperature guage, it should begin to lower as the coolant starts to circulate.
3. Usually within a few minutes the radiator fan will kick.
I hope this helps you.
Feb 02, 2011 |
1999 Ford F150 Regular Cab