Heater - New Design Fan Housing
NUMBER729
GROUP
87
MODEL
700
TITLE
MODIFICATION OF HEATER FAN
HOUSING; A/C, ACC
760 -->1987
740/780 -->1989 (PARTIAL)
MARKET
US and Canada
DATE
January 1993
REFERENCE:
TP 31127/1 (ENGLISH); 09/88; BODY FITTINGS, INTERIOR, CLIMATE UNITS
New fan housing modification for earlier type of blower motor
Heater fan housing P/n 133428-1 has been superseded by p/n 3537209-3 (new design) as a replacement part. When installing an earlier blower motor in the new type of housing, the housing must be modified as described below. See SB 87-930 for procedure for installing a new blower motor in the earlier type of housing.
This procedure applies to:
- 760 with ACC up to and including 1987
- 740/780 with A/C, ACC and ECC up to and including the following chassis numbers (1989) that have the original (earlier) blower motor installed:
REQUIRED PARTS:
Caution:
Switch off the radio before disconnecting the battery ground lead to prevent damage to the microprocessor.
Turn ignition off
Remove/disconnect:
- battery ground lead
- panel under glove compartment
- glove compartment
- door sill moulding
- control module panel
Note:
Take care to avoid damage to panel
- control module connector
- control module mounting screws
- control module
- control module bracket
Remove/disconnect: (from original fan housing)
- blower motor and resistor leads
- screws holding lower section of fan housing
Note:
Two of screws in lower section are concealed between fan housing and evaporator housing
- lower fan housing assembly
- remains of sealing compound from heater
- outside temperature sensor connector (on cars with ACC).
Note:
Special care must be taken when undoing connector to avoid damaging special catches on connector pins.
Remove/disconnect: (from original fan housing)
- drain pipe seal
- electrical connectors
- blower motor and cooling hose
Clean fan housing motor joint face.
Inspect rubber seal to ensure that it is not fitting loosely around evaporator. If necessary, clean and apply adhesive to seal. (Illustration shows evaporator fitted with seal.)
Cut/drill: (in new fan housing)
- 25 mm (1.0 in) dia. hole for outside air sensor if model is equipped with ACC. Use hole saw. Determine positon of hole in original housing and transfer dimensions to new housing (e.g. by measuring off A and B is illustrated) to ensure identical location.
- two 3 mm (1/8") dia. holes for sensor mounting screws. Use sensor connector as template check sensor fit
- remove fan housing cover.
If original fan housing is not intact in shaded area (see illustration), the blower motor must be replaced with p/n 3537854-6 or 3537857-9, and the remainder or this modification does not apply.
If original fan housing is intact in shaded area (see illustration), continue with the following modificition:
Take template and original ran housing. (see attachment)
Copy template. Cut out copy and attach to housing so that edges of holes in template and housing coincide. Mark off cutting line on housing a line outside edge of template (as shown by dashed line in illustration).
Note:
Mark out straight past, not around hose connection branch.
Remove template and cut out enlarged opening. Use power jigsaw or cut manually with hacksaw blade along marked line.
Note:
Cut-out section is referred to as reinforcing piece in following text. The piece is used to reinforce motor mounting in new housing when installing original motor.
Cut: (from new fan housing)
- three motor locating pins with hacksaw (Cut pins flush with housing. See shaded areas in illustration.)
- file cut surfaces smooth.
Remove: (from new fan housing)
- raised edge around outside of opening. Use Knife.
Remove raised edge inside new fan housing.
Remove raised edge around inside of opening. Use knife.
Enlarge hole in new housing.
Drill out hole for motor cooling hose in new housing to diameter of 18 mm (11/16") (or enlarge by hand using round file).
Remove motor locating pins.
Remove two motor locating pins from reinforcing piece with knife (see circled areas in illustration).
Fit reinforcing piece inside new housing. Cooling hose connection should project freely from enlarged hole (i.e. without strain on connection).
Check and adjust as required.
Seal cooling hose connection.
Seal around connection with strip of butyl tape. Sealing is required to protect against moisture.
Drill rivet holes.
Locate holes correctly using stars (A) on template (arrowed in illustration).
Note:
Do not drill out motor locating pin positions.
Install reinforcing piece inside housing and fix in correct position using clamps or similar means.
Note:
Ensure that edges of holes in reinforcing piece and template coincide with opening in new housing.
Drill 3 mm (1/8") dia. hole through template, fan housing and reinforcing piece for each pop rivet. Fold back template, but leave fixing devices in position.
Install pop rivets.
Install reinforcing piece permanently on inside of housing using pop rivets (p/n 965599-4) in the two holes. Remove fixing devices and template.
Drill
Drill 3 mm (1/8") dia. holes through motor locating pin positions from inside housing.
Install butyl tape and blower motor
Place strip of butyl tape around motor joint face to seal with housing and install blower motor.
Mount fan housing cover.
Mount cover (previously removed) and rotate fin wheel. Check fan wheel clearance and inspect drain pipe seal. Replace seal as required (p/n 3522821-2).
Apply sealing compound.
Fill grooves in lower fan housing and housing cover joints with sealing compound (see heavy line indicated by arrows in illustration).
Grooves should be filled completely to ensure satisfactory sealing when fan housing assembly and lower section of housing are reinstalled, and joints are tightened.
Assemble housing.
Install lower section of fan housing and tighten in position. Reconnect motor and resistor connectors.
Adjust position of wiring harnesses.
Reinstall/reconnect:
- control module bracket
- control module
- control module connector
- battery ground lead
Test blower motor operition.
Run blower motor at high speed to blow out any loose remaining debris.
Reinstall:
- control module cover panel
- door sill moulding
- glove compartment
- panel under glove compartment
- reset clock, radio, etc.
Oper. No. Labor Description Time Allowance
873334 New fan housing, 2.0 hr
R & R and modification
for earlier type of blower motor