2000 lesabre


#1

my little ole lady neighbor has a 2k lesabre thats running hot. the temp gauge never goes above half way but u can tell its hot. I’ve changed the thermostat, temp sending unit, and removed and checked the H2O pump, and the elec fan relays, good.

But the fans only run when the engine if OFF! And is doesn’t feel like fluid is pumping through. I thought if the water pump was working it would have to pump water but is just doesn’t feel like it.

I’m stumped.


#2

How can you tell it’s running overly hot? A properly operating engine may run at 220F to 230F when warmed up. The thermostat opens to the radiator at 190F degrees; but, that doesn’t keep the engine from (safely) reaching 220+F degrees.
You won’t feel the water pump pulsing in the upper radiator hose until the thermostat opens. Then, it’s a matter of sensitivity of touch.
The radiator cooling fans may be set to come on at, say, 230+F. The engine may only reach that temperature during the usual heat soak after engine shut down.
To tell what temperature an engine is, you need an infrared thermostat to take a reading from the radiator.
If the cooling system has that red Dex Cool brand antifreeze in it, drain it, flush it, refill with anything else (probably green).


#3

If the water level in the reservoir doesn’t rise above the full hot mark, the engine is not overheating. If the thermostat is blocked, you sometimes hear thumping noises as the water surges into the radiator. You have to run the engine for twenty minutes before you will experience overheating, and you would see the temp go into the red zone of the gauge. It may not be broken. If it isn’t broken enough, you can’t fix it.