Need to locate where my 2001 cadillac deville thermostat Car is not overheating but is running hot not all the time I want to change my thermostat
The thermostat in the northstar engine is located at the bottom radiator hose (unlike most conventional cooling systems), the hose connects into the housing where you will also find the water pump.
You will need to remove the air filter housing and air duct to gain easy access to the thermostat.
Remove the hose from the housing,then remove the two bolts on the flange,the thermostat can then be pulled out.
Take note of the orientation of the thermostat as you remove it.
The thermostat in the Northstar engine is a duel action device.
One end of the stem is the Thermostat(obviously) and at the other end is a spring loaded pressure valve(the thinner end).
Make sure the thermostat end is nearest the rubber hose and the pressure valve end is in towards the engine.
Don't forget the new gasket when you install your new stat, you may have to order this separately.
The most common overheating problem with the Northstar engine is a blocked purge line(small hose).The purge line is designed to purge air out of the cooling system.
There is a small diameter hose coming from near the top of the coolant tank (not the cap) ,this is the purge line.
With the engine idling,pull the purge line from the tank,if there is no coolant flow from this small hose,it is blocked and this will cause overheating.
If the hose is clear, check for blockage at the nipple on the tank.Or trace the hose back until you find the blockage.
The hose goes in to the engine to a crossover and comes out the other side close to the thermostat housing,the blockage may be there.
Also note that the cooling fans don't come on until the coolant temperature hits around 225 degrees.
During normal highway driving the fans will very rarely come on(if at all) due to constant air flow through the radiator.They will only usually come on in heavy traffic conditions on a hot day.
But......if you have the Air Con switched on, the fans will run all of the time.
Nov 05, 2009 |
2001 Cadillac DeVille