Accessory Drive Belt - Jumps Off Pulleys At Low Mileage
Article No. ACCESSORY DRIVE BELTS - 4.9L - JUMPS OFF
87-7-22 PULLEYS AT LOW MILEAGE
LIGHT TRUCK: 1987 F SERIES, BRONCO
ISSUE: Accessory drive belts coming off pulleys at low mileage (less than 50 miles/80 kilometers) may be caused by a mismachined air conditioning/power steering pump bracket. This mismachined bracket may cause the belt tensioner to be misaligned resulting in the accessory drive belt jumping off.
ACTION: To correct this, install a new level air conditioning/power steering pump bracket (E7TZ-2882-A) and an accessory drive belt (if lost or worn) using the following diagnostic service procedure. Refer to the accessory drive belt application chart on page 33 of this TSB for correct service part application.
1. With hood open, transmission in PARK, and parking brakes on, run engine for five (5) minutes increasing engine speed to 3000-5000 RPM every minute for 5-10 seconds. Idle engine and see if accessory drive belt is riding on all pulleys correctly; most of all at belt tensioner and power steering pump pulleys. If not, this vehicle may have a bad air conditioning/power steering pump bracket.
2. Remove accessory drive belt by relieving belt tension at belt tensioner by lifting tensioner pulley drive bolt with a 16 mm socket on a breaker bar as shown on installation decal on radiator shroud.
3. Remove fan blade and radiator shroud.
4. Remove belt tensioner - one (1) bolt at center of tensioner.
5. Remove power steering pulley.
6. Remove power steering pump - three (3) bolts. Do not disconnect power steering lines, it is not necessary.
7. Remove four (4) bolts from air conditioning mounting compressors and remove compressor. Do not disconnect air conditioning compressor lines, it is not necessary.
8. Remove air conditioning/power steering pump bracket - four (4) bolts at engine block, two (2) bolts at cylinder head.
9. Install new air conditioning/power steering pump bracket.
NOTE: A bolt/nut torque sequence is important. Position bracket without accessories and finger tighten all bolts/nuts. Torque front locator leg (thumb) bolt to cylinder head first 24- 35 ft.lbs. (32-47 N-m) and torque the rear foot at the cylinder head to 24-35 ft.lbs. (32-47 N-m) next. Torque the four (4) bolts/nuts at engine block to 38-55 ft.lbs. (51-74 N-m).
10. Reinstall air conditioning compressor.
11. Attach power steering pump to bracket. Torque to 30-45 ft.lbs. (40-61 N-m).
12. Install power steering pump pulley to .020 + .010 inch over press (past end of shaft).
CAUTION: Do not hammer pulley on.
13. Attach belt tensioner. Torque bolt to 65-85 ft.lbs. (88-115 N-m).
14. Install fan blade and radiator shroud.
15. Install original drive belt or new belt if found damaged. Wrap belt around all pulleys as shown on installation decal on radiator shroud putting belt over steering pump pulley last. Position belt tensioner by using 16 mm socket and breaker bar on pulley bolt by rotating clockwise. This will lift pulley up allowing belt to slip over power steering pulley. Release belt tension slowly.
CAUTION: Do not release suddenly. This could snap off tensioner stop. Inspect to see belts are fully on each pulley. This is best done by feeling each pulley for belt overhang with finger.
16. Run engine and inspect.
17. Log Vehicle Identification Number (VIN) for engineering use.
ACCESSORY DRIVE BELT APPLICATION CHART
Application Service
Part Number
F Series/Bronco with manual
transmission, air conditioning, and E7TZ-8620-C
100 amp alternator.
F Series/Bronco without air
conditioning and with a 60 amp E5ZZ-8620-A
alternator.
F Series/Bronco with manual
transmission, air conditioning, and E7TZ-8620-D
60 amp alternator.
F Series/Bronco without air
conditioning and with a 100 amp E7UZ-8620-A
alternator.
F Series/Bronco with automatic
transmission, air conditioning and E2DZ-8620-B
60 amp alternator.
F Series/Bronco with automatic
transmission, air conditioning and E7TZ-8620-A
100 amp alternator.
PART NUMBER PART NAME CLASS
E7TZ-2882-A A/C and Power Steering C
Bracket
E7TZ-8620-A Drive Belt B
E2DZ-8620-B Drive Belt B
E7UZ-8620-A Drive Belt B
E7TZ-8620-D Drive Belt B
E5ZZ-8620-A Drive Belt B
E7TZ-8620-C Drive Belt B
OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: Reimbursable within the provisions of the Warranty and Policy Manual
OPERATION: SP870722A
TIME: 1.4 Hrs.
DLR. CODING: Basic Part No. 2882 - Code: 85