I just bought this truck last week and I'm trying to work out all the kinks. First thing I need to do if figure out why my heat is not working. They recently replaced the radiator and I replaced the t-stat. The two heater hoses that go to my heater core thru the firewall are not hot. Why??
The upper and lower radiator hoses are both hot at operating temps. I wish I could get this figured out.....does anybody have any ideas???? thanks.

 

make sure your valve moves when you adjust from cold to hot.
inside the engine bay, on the firewall, really high, is a push-pin valve and you can see it move when you move the cold-hot lever inside the dash panel.

if that valve doesnt move, or is broken/bypassed/disconnected, you will not get the water to flow through the hoses.


mine flows, but the heater core is not working correctly (common problem)

 

anouther thing to check..go to the pasenger side look at the glove box underneeth the glove box to the left kinda tucked in there and close to the floor is a valve operated by the dash controls via a cable, i forget if you push for heat or pull try eather or. i froze my but off or a winter untill i found this

 

I saw this valve and it seems to be connected correctly. How do I know if its broken or opening properly?

 

Pull off the outlet or inlet side of the hose and look in it while manipulating the lever.

 

Ok now I feel stupid .....that makes sense....thanks I will try that.

 

My heater quit working once after I replaced the t-stat, appearantly after refilling with coolant the system had an air pocket that stopped the coolant flow to the heater core. After I drained the coolant and refilled with the front end jacked up and the throttle coolant hose pulled off to burp the system the heater started working fine.

 

Oh yeah....that's quite common. Good point.

 

I have ahd the same thing with the air pocket. I just pulled the outlet hose when it was running and that got the air out. Messy but I was cold.........

 

I checked the heater control valve and its working fine, then I drained and refilled the coolant while making sure all the air was burped out of the system. Still no heat. I'm lost.....what should I check/replace next?? Heater Core??? Thanks.

 

You said the hoses going into the firewall (to the heater core) are not getting hot? Sounds like air in system (can be a major PITA sometimes to burp) or bad water pump.