why doesn't my heat work

air blows fine, heat just didn't work. I filled the radiator, nothin. replaced the thermostat, nothin, next is going to be the heater core witch Im not looking forward to doing. just wondering if there's anything I should check before going into the heater core. and how hard is it to replace the heater core of that's Wat the problem is. also my temp guage doesn't go up, it moves up to the c on the temp guage, any reason why that is.

This discussion just occurred over on MT. It might be your controller or the valve on the heater core.

Have a look here.

Are both the heater core inlet and outlet both hot after driving 15 minutes?

I haven't checked, what does it mean If they are or not

If not hot you may have a blockage or bad water pump/thermostat/radiator cap.

If both don't get hot in like 15 minutes, the issue is with the engine.

If one gets hot, heater core could be plugged partially or full.

If both get hot but you still don't get decent heat, issue is inside the dashboard.

I had the same issue a while back. As the experts above said, if the hoses aren't hot, (even just a little warm doesn't count), your core is plugged. Mine was plugged. Dash removal is unbelievably simple on these Bs. There is a detailed write up with pics on dash removal here:

I used that write up to remove the dash to get to my heater core. What I did to unplug mine was I spent about 30 - 45 minutes of running kerosene through to eat the gunk while using compressed air to try and blow out the gunk. BE CAREFUL NOT TO PUT YOUR FACE OVER EITHER END OR ELSE YOU'LL GET A FACE FULL OF KEROSENE AND GUNK!!!

I would suggest afterwards, you first run some antifreeze through the core to remove any traces of the solvent. Next, I'd clean the outside fins with some water and spray it with an air freshener. Otherwise, your truck will smell like solvent for a whole winter or two.

I had no heat for the longest time, but this fixed it.

And if plugged, usually better to flush out in reverse direction to get it clear.

I have had a repeating issue with my B, to where the temp selector knob seems like its working but in fact is not actuating the blend door due to a broken part directly attached to the knob in the dash...

Its a plastic mechanism that pulls or pushes the cable to the blend door. still gives resistance and clicks when turning the knob but the plastic housing is broken internally.

It stays in the position where it broke, so if it broke on the cold setting then it will stay on the cold setting and visa versa.

Check out this thread on MT. post #15 is where Earl took some great pics of the part broken/ not broken. I have replaced mine twice.

When you replace those "switches" make sure you lubricate the gear with white lithium grease and try not to turn it past or forcefully to the natural stopping point of the switch during normal operation. I know sometimes I grab it and twist quickly and then think, easy big fella....