heater problem with heater control valve vacuum line
ok, here is the history
replaced water pump
put it back together and no heat.
Noticed I'm not getting any vacuum to the heater control valve (HCV).
flushed the heater core, and put it back together. Had vacuum and heat for
about 5 minutes. then HCV opened (no vacuum) and no more heat.
Read some other replies here, and seems to be some experienced Ford
AS you know...Most Ford explores have a vacuum operated valve in the heater line to the heater. It is located on the passenger side near the back of the engine in one of the heater lines. You should be able to move valve with your hand. Once engine is up to temperature, feel both sides of heater hose before and after valve. it should be hot on both sides if water is flowing. If not move valve and see if it gets hot on both sides. If that it is the problem, just prop valve open until you can replace it. NEXT...I would also check your BLEND door , Fords are known for BLEND DOOR issues
You have air in the heating system. WITH THE ENGINE COLD... Take the coolant resvoir cap off. Turn the engine on. Let it get hot by touching the upper radiator hose. If its hot the thermostat is open. Grab a shop rag and carefully squeeze the upper raidiator hose until you dont here bubbles or gulps coming from the coolant resevoir. This will bleed the air out. Every so often get in and rev the engine to get the water pump to circulate the coolant and air throughout the system while your doing that turn the heat on and place your hand by vent to feel the hear. When you grab the upper hose bubbles should come from the resvoir. Remember once the resivor cap is off its vented to the atmosphere so its not going to overheat or hurt you but DO NOT TAKE THE CAP OFF THE RADIATOR JUST THE RESIVOR.
I agree the cooling system may need to be bled from air,
will give it a try.
Looking for a Used Explorer Sport Trac in your area?
CarGurus has 2,084 nationwide Explorer Sport Trac listings starting at $1,999.
Search Ford Explorer Sport Trac Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Ford Explorer Sport Trac Experts