Our mercury sable 1993 keeps overheating

Most likely it is a clogged heater core. Have your heater core reverse flushed or your blend door is stuck open.

"rule out" questions - is coolant level OK? Any leaks, especially around the water pump? Has the system ever been flushed. out? If this is the original radiator, it could be clogged. Is the thermostat installed correctly with spring end toward the engine?

Hello,
I read your problem and what you have done to try and rectify the problem. Let me say this first. You did a great job of trying to fix this over heating problem. There is only a couple other things to check or have done to solve this overheating problem. Only other things it can be that cause it to over heat is Number one, make sure your temp sensor is operating proper, you can have this checked by any repair shop, they will check with a amp meter. And assuming you do not have a head gasket leaking, which would cause over heating, what i would do is have the radiator system flushed, and put under pressure. Reason for this, is a lot of times, radiator gets some what partially clog, this is due over time from not proper antifreeze and water ratio. Internal parts and coils of radiator become partially clogged as things break down inside. First thing, i would suggest if to have radiator flushed and then see if it flows correctly via the new thermostat you just put in, and of course the water pump is providing the proper flow of operation. If that does not work, have them check the coolant sensor, to make sure it is triggering correctly to allow the thermostat to operate normally. I hope this helps, Thank You, Mike

Check the thermostat. The temperature sender is to the right of the thermostat and if the thermostat doesn't open the hot coolant from the block won't be flowing to the sender/gauge showing it is overheating. The thermostat is at the end of the top radiator hose where it enters the engine. Check the wires to the sender to make sure they are connected. Flush the coolant and heater core at the firewall connections as it may become clogged.

Remove and raise upper hose at thermostat end and remove lower rad hose.
Fill rad with a hose and watch for flow from bottom rad hose and/ or bottom rad hose connecton.......water should fall though rad easily.
Honda rads are cheap.....any restriction....replace rad.

Remove thermostat....fill thermostat housing with hose and watch for water flow at bottom rad hose.
Flush good.

Remove heater hoses.......flush back and forth until a good flow is present "With heater control set to hot" if no or poor flow....replace heater core.

Stop leak can plug everything.

Also.......not likely causing over heating....but ....at your mileage,if you do not know if the timing belt has been changed.....CHANGE IT NOW!
Water pump is optional at this mileage.

Well there's only part that has to do with the cooling system and serp belt - the water pump!! Maybe it's starting to seize or has too much play. Either way, when you change the water pump, replace the thermostat and flush the system very thoroughly, those 98-99's are notorious for rust build up. Make sure to pull the heater hoses off and flush the heater core too. After all said is done, purge the coolant and make sure there is heat from the blower. If not you're going to have to replace the heater core because that gets clogged sometimes when flushing.

sometimes the radiator is just too plugged to respond to flushing. (happens a lot with a marginal radiator because when flushing, the solvent simply goes around the plugged area, and cannot build up enough force to break it free). From what you have written, this may be the case. Is the electric fan coming on and off at the right times? if not this also can give you similar problems. You have done the right things but may not have gotten the desired result. Hope this info helps you a bit.
good luck

Good Day,

White some indicated that coolant is burning off. It could just be a simple leak which is burning off of the hot motor. It could also be a bad head gasket(probably what you don't wanna hear), One indication that it is the head gasket is white smoke coming out of the exhaust, this happens as coolant gets into the oil and is burned off then exhausted out the back. Possible causes for the overheating include, low coolant, coolant leak, thermostat, water pump and or water pump belt, or head gasket.

If I were you I would drain and flush the radiator, then fill it with new coolant, and change the thermostat, provided you have no white smoke coming out the exhaust.

hope this helps for now

if you are sure all of the above is correctly installed then the only othet thing i can think of if it isnt loosing coolant is either the guage or the sender unit is faulty,
if its not loosing coolant and the radiator isnt filled with muck then it really cant be anything else.
one other thing might sound silly but check that the thermo fan if its got one is coming on or if there is a plastic bag or something blocking the radiator

does the car make a squeking noise when you start it?