Vintage Mustang Forums banner
  • Hey everyone! Enter your ride HERE to be a part September's Ride of the Month Challenge!
1 - 8 of 8 Posts

·
Registered
Joined
·
139 Posts
Discussion Starter · #1 ·
I'd welcome advice on aligning the heater control cables.

Both heater control levers were very hard to move. Neither had full range of motion. I had the dash apart for a variety of reasons, and removed the heater control assembly to lube the cables. Quick aside -- used WD-40 and a motorcycle cable luber. It made a big difference. Both cables now guide effortlessly in their sleeves when the heater control levers are moved back and forth.

Cool-heat cable: There's a hard rubber section, slightly larger in diameter, about an inch away from the end of the cable. When I position this hard rubber section over the clamp, the cable is too long, i.e. extends beyond the rod on top of the heater box. I got it to work, but should I be concerned that it isn't clamped in the proper place?

Heat-defrost cable: Same problem, i.e. the hard rubber section will not align with the clamp on the plenum. However, this lever requires much more pressure. No matter where or how I clamp it it won't work well. So much force is required to move the lever that it starts to bend. Do these cables stretch?

Again, any advice appreciated.

Reference photos...

http://home.wideopenwest.com/~slagreca/Mustang/Cable-warm-cool(Small).jpg


http://home.wideopenwest.com/~slagreca/Mustang/Cable-heat-defrost(Small).jpg
 

·
Registered
Joined
·
1,712 Posts
I am willing to bet that your problem has little to do with the cables, and that the root cause is a heater plenum box that needs reconditioning. Inside the plenum box there are two doors that the cables operate to route the flow of hot air. These doors have seals that probably need replacing anyway... and a rebuild kit is about $10.

I think you will find that if you remove the cable all together from the metal arm protruding from the heater box you will find it very difficult to operate the lever. Crud and corrosion from the last 40 years have most likely taken their toll on the flapper door mechanisms... clean them up, lube them, replace the seals, and make sure the doors operate smoothly before attacking the cables.

Good luck,
-Rory
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #3 ·
Thanks 2ndGen! Makes sense. IIRC, this requires pulling the heater box assembly. Guess it's time to to tackle it.
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #4 ·
Help pls, I'm stuck. Can't get my non-A/C heater box assembly out from under the dash. I've removed the dash pad, defroster duct, heater duct, glove compartment, hoses, cables and wires. The heater box is loose from the firewall. It's too big to "wiggle out" from under the dash. I've located, read and followed two sets of instructions. Oh, pls tell me there's a way to do this *without* removing the lower dash.
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #5 ·
Got it. What a PITA. It took two more steps. First, open heater box and remove the heater core. Next, remove 2 bolts on passenger side of dash. It was a tight fit, but I was able to wiggle the box from under the dash. Now, onto the flapper doors...
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #6 ·
Flapper door was sticking due to buildup of dirt and rust ... and that the rubber seal was dragging *hard* on three sides. After cleaning and careful trimming the door moves effortlessly.

The flapper door doesn't seal against the sides quite as tight -- might have introduced a bit of air slippage -- but it's an acceptable trade-off.

On to replacing gaskets...
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #7 ·
Good advice on the gaskets seal. The seal kit came with 12 seals in all. Over half were either partially rotted or completely missing. Reassembling now...
 
1 - 8 of 8 Posts
Top