A/C Controls - Sticking or Binding
87ford01
^ HEATER CONTROLS - STICKING OR BINDING - Article No.
VEHICLES BUILT BEFORE 02/24/87 87-13-19
^ AIR CONDITIONING/HEATER CONTROLS - STICKING OR BINDING -
VEHICLES BUILT BEFORE 02/24/87
LIGHT TRUCK: 1986-87 AEROSTAR
ISSUE: Sticking or binding heater or A/C/heater controls or excessive air bleed may be caused by the FLOOR-PANEL air door binding or not closing all the way inside the plenum case. This may cause air flow to be discharged from the wrong outlets and/or excessive air bleed through the instrument panel registers when the control is set for the air to be discharged elsewhere.
ACTION: If air flow is discharged from the wrong outlets, shim the FLOORPANEL door as outlined in Part I of the following service procedure. If excessive air bleed exists, adjust the air control cable as outlined in Part II of the following service procedure.
NOTE: Vehicles built after 02/24/87 have a new vacuum control system to operate the air doors. This new system will eliminate the binding condition.
Figure 14 - SHIM LOCATION:
PART I
1. Remove heater core cover from plenum.
2. Clamp off heater hoses and remove heater core from plenum.
3. Remove FLOOR-PANEL door gear and remove binding FLOOR-PANEL door from plenum case, Figure 14.
4. Sand the sharp edge of FLOOR-PANEL door shown in Figure 14.
5. Apply a silicone base lubricant to sanded edge of door and the contact area of the case, Figure 14.
NOTE: Do not apply lubricant to foam gaskets. They will become sticky and cause increased door efforts. Apply lubricant sparingly to avoid dripping or gumming.
6. Position the sanded and lubricated door in the case. Install one or two (1 or 2) 1/4" flat washers over lower pivot pin of FLOOR-PANEL door and install door. This will raise the bottom of door and prevent it from binding against the plenum case. Normally, total height of the washers required will not be more than about 1/8". However, more or less washers may be needed depending on the amount of binding.
7. Lubricate cam and gear linkage sparingly with a silicone base lubricant to reduce lever efforts.
8. Adjust control cables to be sure of correct air distribution.
Figure 15:
Figure 16:
9. Check the air door for ease of operation. If operating efforts are reduced to an acceptable level, install heater core and heater core cover. If operating efforts are not reduced, remove gear and FLOOR-PANEL door and compare door and gear to Figures 15 and 16 to determine if they are the latest design. Replace door and gear if they are not the latest parts.
10. If door and gear are replaced, check control efforts to see if sticking or binding still exists. If the stick/bind is corrected, install heater core and heater core cover. If a stick/bind condition still exists follow the procedure outlined in TSB article 86-9-15.
PART II
1 . Position the Function Selector Lever in the OFF position.
2. Disconnect the BLACK function cable from the SILVER cable clip at the plenum.
3. Install a 1/8" diameter pin or drill bit in hole of plenum cam, and mating hole in case.
4. Move Function Selector Lever about 1/8" from OFF position toward VENT position. This will move BLACK cable housing about 1/8" rearward from its original position in the cable clip.
5. Secure cable into SILVER clip and remove pin installed in Step 3.
6. Operate system and cycle Function Selector Lever to check for reduced air bleed. If not reduced, repeat adjustment while positioning the Function Selector Lever 1/4" from VENT position.
7. Again, operate system and check the panel air-bleed.
PART NUMBER PART NAME CLASS
E79Z-18A497-A Gear A
E79Z-18A559-A Door B
44719-S2 Washer - Package S
of 150
OTHER APPLICABLE ARTICLES: 87-6-11, 86-9-15, 87-13-18
WARRANTY STATUS: Reimbursable within the provisions of the Warranty and Policy Manual
OPERATION: SP871319A - Part I
TIME: 1.3 Hrs.
OPERATION: SP871319B - Part II
TIME: 0.6 Hr.
DLR. CODING: Basic Part No. 18A559 - Code: 41