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2000 B2500 heater won't heat.

  #1  
Old 05-11-2017, 09:30 PM
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Default 2000 B2500 heater won't heat.

Hello all,
My sons 2000 B2500 heater won't heat. The heater core started leaking a few years back and was bypassed. I started working on today, some 4 years later. I've replaced the heater core, thermostat and cleaned all the hose, also replaced the diverter. Still no heat, replaced the potientalmeter and cut into the duct to check the blender door. It's working but still no heat. Tried burping the system to get any air out still no heat. The water flow just past the thermostat seems very slow, I'm starting to think the water pump is bad but it's not leaking and no over heating. Every water pump I've ever replaced started leaking or the engine overheated, none of that is happening. Any thoughts on what could be the issue here, I'm at a loss???
 
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Old 05-12-2017, 08:02 AM
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When the engine is warmed up (say 10 minutes of driving), feel both the inlet and outlet hoses to the heater at the firewall, both should be hot.

This will help diagnose your issue. First you must find out if hot coolant is passing through the heater core (could be engine issue, blockage, or a valve shutting off the flow) or not.
 
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Old 05-12-2017, 10:04 AM
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Tried that they are warm but not hot. I do have vaccum to the diverted valve. Still seems like the volume of fluid going thru core is low.
 
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Old 05-13-2017, 09:35 AM
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Agree: think best to focus on the engine coolant flow volume.

2000 truck is essentially clone of Ford Ranger, way more of those around, maybe try Ford Ranger forums.
 
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Old 05-13-2017, 09:40 AM
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Originally Posted by Cusser View Post
Agree: think best to focus on the engine coolant flow volume.

2000 truck is essentially clone of Ford Ranger, way more of those around, maybe try Ford Ranger forums.
thanks cussed, I have been reading the ranger forums. This has got me stratching my head. The core was bypassed some years ago, I'm looking for something else they did that would prevent the core from getting water. Just seems like the air conditioner is on, I even unplugged the compressor and felt the temp go down?
 
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Old 10-29-2017, 07:32 PM
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Update, replaced the water pump. All the fins were gone. Installed a new thermostat as well. Still getting cool air and the AC condenser is cycling on and off when air blowing through dash and floor vents. I even unplugged the condenser and pulled vacuum on the diverter valve but it got a littler warmer but by no means not heat. Any ideals?
 
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Old 11-02-2017, 11:14 AM
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Originally Posted by dugger View Post
Update, replaced the water pump. All the fins were gone. Installed a new thermostat as well. Still getting cool air and the AC condenser is cycling on and off when air blowing through dash and floor vents. I even unplugged the condenser and pulled vacuum on the diverter valve but it got a littler warmer but by no means not heat. Any ideals?
Actually, you mean that the AC compressor is coming on, not the condenser.

Still, the AC compressor is only designed to come on in the AC mode, and in the Defrost mode (to remove moisture from cabin air). So there might be an electrical problem there. What temperature is your new thermostat? I run factory 192/195F in my '88 Mazda truck, wasn't getting enough heat with a lower set thermostat. Also important to bleed off ALL the air from the cooling system; I jack up the front of my truck, take the radiator cap off, and run the engine with heat on and keep adding 50/50 coolant as necessary.

Wow that the impeller fins on the water pump were corroded/gone !
 
  #8  
Old 11-20-2017, 07:39 PM
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Thought I'd update everyone on my no heat issue. Finally burped the system enough that I'm getting good heat. Really took some time to get this done. Pushing water with the hose and removing one of the hoses at the heater core did the trick. Now if I can get the P0171 code, (ERG) fixed. I've replace the ERG,DPFE and checked all the vacuum hoses. Truck still kind of stumbles coming out of first sometimes and appears to be burning more fuel than it should. Replaced the fuel filter which was really needed. Gonna check fuel pump presure tomorrow. It thats good I'm thinking the intake gasket, tried using some carb cleaner but it didn't change anything. Any ideals?
 
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