water pump may not be worn out, heater core may be clogging
A blocked heater hose could cause a leak. A stopped up heater core could as well. Or the connector in the Windstar could be cracked.
That or the thermostat.
i replaced my heater core and it has been fine ever since (8 months )
the thermostat is probably not functioning properly...replace thermostat and see if the situation is resolved. Easy cheap fix. Check your coolant level before replacing the t-stat. You may just be low on coolant.
Thermostat.....
well no damage will really happen the thermostat allows the motor to get to a warm temp with out one the motor will (should) run slightly cooler but in the winter months the heater will not work very good.
you might want to try flushing your radiator fluid. If it has been a while the corrosion in the water can will cause your thermostat to malfunction. also as a suggestion could be the blend door th actuator is on the heater housing at about knee level on right leg check that
Heater plugs in a ford focus 1.8 engine should be changed every 18 months-2 years.
The thermostat you installed was either bad or is installed upside down. Possibly a clogged heater core. Possibly the system needs bleeding.AnswerCould be your control cable is broken. Not familiar with your particular model but look for a cable on or near the firewall near the heater core. You may be able to move it by hand and get the haet you need. AnswerRemove DEX coolant the manufacturer recommends. DEX clogs the heater core. Put regular coolant in it then drive, drive, drive. It will break loose. Mine took nearly 4 months to get the sludge out of the radiator even after flush. But it worked. Manufacturer will never comment about that DEX crap. I have a 98 and I had the same problem..it was my heater core, they arent hard to replace and I dont think they are that expensive
Replace Heater Core
It just changed to 6 months
Heater filters should be replaced every 3 months for optimal performance.