76 MGB heater airflow /defroster cable

I installed my dashboard the other day after being out of the car for 6-7 years. When hooking up the cables and wire connectors, I did not have a cable to attach to the rotary switch for the air vents/defrosters. I think that when I installed the heater core & fan assembly I should have installed a cable with it. It's been about 2 years since I installed the heater box in the engine bay. Am I correct in thinking there should be a cable going into this from the cockpit? If so, can I install this cable with out removing the heater box. If I am wrong, where does this cable from the switch attach at the other end? Any pics of the inside of the heater box would be helpful along with any other advise on this cable. Thanks

You can instal the cable with the heater box in place. Its a bit of a PITA, (but what isn't?)

As you said, one end connects to the dial and the cable feeds behind the lower console, through the heavy rubber gasket and connects to a small lever at the base of the heater box. You can reach the connection through the heater outlet in the passenger side footwell...really.

If its there, remove the small black plastic air director thing and shine a light into the airway. The cable can then be fed into a hole in the lever and made fast with the same kind of gadget that is used on the other end of the cable and alot of other places where cables are fixed...like the hood release, choke cables, etc.

Its real tight but it CAN be done. I know from experience.

Somebody posted a picture looking into the heater vent. Did you do a search...good luck.

This may be the picture? by GeeMoo

You can hook the cable up with it in, as it was said. Be sure to have a magnetic screwdriver/magnetic pick up tool, a warm dry place to play, and a LOT of time. I would also suggest not letting any kids be around. They may learn a few new words.

Take off the deflector on the passenger side, and it should become obvious What needs to be done.

Good luck.

Thanks, just the info I was looking for. Never thought to look behind that deflector.

Thanks for the help from all those who replied and those that would have replied if they got here 1st. I got the cable installed, not as bad as I was expecting. Of course it helps that my seats are not yet installed and I could lay on the floor to access the mechanism. Although the vent hole in my B is about 1/3 the size of the one pictured above. THANKS AGAIN. I don't know where I would be if not for the terrific help I have received from all of you here at the MGB Experience.