Why would it be necessary to bleed a cooling system and if so how is it done ? I am going to flush and refill system anyway so will that do it ?
Jan 18, 2016 at 5:04 PM
bleeding air from radiator
1997 FORD ESCORT
DONPRUETTE
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CARADIODOC
- ✓ASE Certified Mechanic
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Some systems bleed by themselves, others don't. Watch the temperature gauge or feel the upper radiator hose to tell if coolant is circulating.
When an air pocket forms under the thermostat, that will prevent it from opening. Thermostats open in response to hot liquid. Hot air won't do it. If you have to bleed the air out manually, look for a bleeder screw on the thermostat housing. If there is none, there will be a temperature sensor or threaded plug on or near that housing that can be removed. Remove something that will let the air out as you add coolant at the radiator. If you have to unplug a sensor, do that with the ignition switch off so a diagnostic fault code won't be set.
When an air pocket forms under the thermostat, that will prevent it from opening. Thermostats open in response to hot liquid. Hot air won't do it. If you have to bleed the air out manually, look for a bleeder screw on the thermostat housing. If there is none, there will be a temperature sensor or threaded plug on or near that housing that can be removed. Remove something that will let the air out as you add coolant at the radiator. If you have to unplug a sensor, do that with the ignition switch off so a diagnostic fault code won't be set.
Jan 18, 2016 at 5:12 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.