Contour Enthusiasts Group Archives Forums General Troubleshooting zetec running hot, need advice

My 1997 Zetec (110.000 miles) has started to consistently run hot. It is always at the L in normal, some times it goes right under the RED.

I have changed the thermostat two months ago. Just tested the new thermostat by putting it in boiling water and it did open.

I checked the belt that runs the water pump, it seems to be nice and tight.

I tried unplugging the sensor on top of the thermostat housing (which makes the radiator fan run all the time) and it didn't bring the temperature down.

I drained all the coolant, ran some water through it and put all 50/50 coolant/water in there. Still the same problem.

1. Could my water pump be failing so that it is no longer as efficient as it should be?

2. Is it my radiator?

3. ???

I don't know where to go from here... any advice?

Thomas

well with 110k a good fluch of the colant system couldn;t hurt things. I have 111k and the only time the temp goes up is after driving on the highway then getting stopped in traffic or getting off the highway. The fan doesn't run very long but it should cool alot. Make sure the fan runs when the AC is on, that would be a quick way to see if the fan works. Also the guages are not calibrated per say. the needle could just be off. If there are no signs of overheating it might be fine but I am not sure on that

Im not familiar with the ztechs...but it sounds like a water pump. I know the Duratechs use a plastic impeller in threre water pumps witch cause them to go out early.

You may want to check to see what kind of impeller is used on the Z tech water pumps. If its plastic I reconmend changing it.....and that might solve your problem. Look in to it....I hope it helps

ROZ

I'd do what Brapple suggested.

Other than that my coolant temperature sensor went wrong last yr showing all kinds of weird readings (it is the sensor in the thermostat house looking DOWNWARDS - autozone calls it as 'coolant temp. SWITCH' - what they call sensor is for the ECU and it is above the thermostat). So it can be simply the sensor.

I also had a (incorrect temp. or simply broken) thermostat once causing similar symptoms.

But the first thing you should do is a good flush.

Tiv

for got to mention that when I changed the timing belt at 104k the water pump didn't so any signs of failure. Unlike the duratec pump it is a more "classic" design and has a weep hole. The pump was die so it is still good, besides there is not a high know rate of ZETEC water pump failures

just systematically check the involved systems and something should turn up

I replaced the temperature gauge sender (or whatever its called, the one on the bottom of the thermostat housing) a while back so it _should_ be ok.

Will get someone to do a good flush that sounds like the logical thing to do.

Thanks guys,
Thomas