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Air Conditioning - Moan and Vibration

Bulletin 87-1-2

Date Nov., '86

Ref. No. 87-032-1
SUBJECT: AIR CONDITIONING MOAN AND VIBRATION

MODELS AFFECTED: 1982-1987 V6 ENGINES, LESS SINGLE DRIVE (SERPENTINE) BELT


Many A/C related noises and vibrations at idle and off idle can be corrected by proper tensioning of the air conditioning belt. If such a condition, with the A/C on, is reported, the belt tension should first be checked with an approved belt tension gage such as Kent-Moore J-23600 and tensioned per chart. When replacing the A/C belt or concluding a repair that requires removal or loosening of the A/C belt, care should be exercised to adjust belt back to proper tension.

Another cause of noise or vibration that should not be overlooked is compressor mounting bracket bolts. Make sure that bolts are to proper torque. Proper bolt torques also apply to single drive (serpentine) belt designs.

V6 A/C BELT TENSION CHART

Engine VIN
Sales Engine A/C Belt Tensions
Code Code Engine Max (New) Min (Used)*

LE2 X 2.8L 650 N 300 N
(150 lbs.) (70 lbs.)

LK9 E 3.0L 750 N 400 N
(165 lbs.) (90 lbs.)

LN3 3 3.8L MFI 750 N 400 N
(165 lbs.) (90 lbs.)

LM9 9 3.8L SFI 650 N 350 N
Turbo (150 lbs.) (80 lbs.)

LC4 4 4.1L 650 N 350 N
(150 lbs.) (80 lbs.)

LD5 A 3.8L 650 N 350 N
(150 lbs.) (80 lbs.)

*Spec. -0 +50 N