repalced water pump- heater not working now?

   / repalced water pump- heater not working now? #1  

goaliedad

Gold Member
Joined
Jan 1, 2006
Messages
354
Location
NORTHWEST MICHIGAN
Tractor
KUBOTA L175
I had to replace the water pump on my Jeep Liberty '03 3.7liter- and now the heater is messed up- blows kind of warm, then cold, back to warm. I drove it about 20 miles- the temp gauge is showing normal. I thin I have an air bubble- but what do I do?
 
   / repalced water pump- heater not working now? #2  
Probably a silly question but have you checked the antifreeze level after the vehicle warmed up and opened the thermostat the first time (after the water pump change)? Are the heater hoses warm or cold? Could be a restriction in the heater core. Low fluid level is my guess.
 
   / repalced water pump- heater not working now? #3  
Your right about the air bubble, it is air bound and needs to be bleed and are you sure your heater hoses are on the correct fittings, that would make a difference also. Try disconnecting the upper hose on heater end and add some water with a hose or something
Jim
:)
 
   / repalced water pump- heater not working now?
  • Thread Starter
#4  
Thanks for the replies- I drove about 10 miles- watched the temp gauge- checked the fluid level- looked ok. Drove back, temp gauge never varied. It was dark and late, so I did not check the fluid- will this morning. I did not disconnect any hoses, so that's not an issue. I hope the air will work itself out- if not, I will pull the heater hose off.
 
   / repalced water pump- heater not working now? #5  
Take off the rad cap off and run it a while and then just leave it sit. Do this a couple of times and maybe the air bubble will move. :confused: :confused:
 
   / repalced water pump- heater not working now? #6  
There might also be an additional bleeder valve in the heater circuit. Some older Nissans and I think the Ford Aerostars with the rear heater have them to help purge the air from the circuit. Follow along all the heater hoses and look for anything plummed into the circuit. If it is installed, purge instructions might be found on a placard or sticker near the valve in the engine compartment, or the underside of the hood. There may also be specific purge instructions in the owners manual...
 
   / repalced water pump- heater not working now? #7  
hopefully you ran the engine after your repairs until the thermostat opened and swallowed some coolant then topped it off again before putting cap on. Otherwise you risk baking things. The heater hoses should both be warm to the touch like the upper hose after its up to running temp. If ones colder it could indicate restricted core. If it was perfect before your job its likely air.
 
   / repalced water pump- heater not working now?
  • Thread Starter
#8  
Thanks for all the ideas- I thought I had ran it long enough after the repair to purge the air- but I guess not. Sunday morning the resevoir was empty, so I filled it up, ran with the cap off until it warmed up, refilled, repeated as needed- all is fine now. Note to self- always run the vehicle for a long time before assuming the radiator is full!
 
   / repalced water pump- heater not working now? #9  
I ran into this problem twice this summer. I had to replace water pumps in 2 of my 3 vehicles (the 2 daily drivers). I wonder if the hotter than normal summer did it?
 
 
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