Alternator - V Belt Slips Under Load
Group: 13Number 92-01
Date: Jan. 31, 1992
Subject:
Alternator V-Belt Adjustment
Model(s):
All Models, All Model Years
Condition
Alternator V-belt may slip under extreme load conditions.
Service
To prevent possible alternator V-belt slippage, the belt tensioning specification and adjustment procedures have been modified.
When a customer complaint of V-belt slippage is encountered, adjust V-belt tension according to the specifications listed below.
Tensioning Specifications
The following values apply when using the "thumb pressure check" procedure.
V-Belts up to 1000 mm (40 inch) long max. deflection
new belts - approx. 2 mm (5/64 inch)
run in belts - approx. 5 mm (3/16 inch)
V-Belts over 1000 mm (40 inch) long max. deflection
new belts - approx. 10 mm (3/8 inch)
run in belts - approx. 15 mm (19/32 inch)
Note:
These values are valid for all vehicles produced to date.
Adjustment procedure:
On engines that are NOT equipped with the tooth rack on the adjustment bracket, tension belt according to above specifications.
On engines equipped WITH the toothed rack on the adjustment bracket, the V-belt tensioning should be performed using a torque wrench:
^ Loosen all securing nuts for adjustment bracket (A) and alternator by minimum of one turn
Note:
After loosening the securing bolts, the alternator must move freely (alternator must drop to the side under its own load)
^ Tension V-belt by rotating the tensioning nut (B) with a torque wrench
^ Torque 8 Nm (6 ft lb)
^ tighten bolt securing tensioning nut
^ Torque 35 Nm (26 ft lb)
^ tighten adjustment bracket support 0P engine block
^ Torque 20 Nm (15 ft lb)
^ start engine
^ run engine for approx 5 min at idle
^ switch off engine
^ retighten V-belt with torque wrench
^ Torque 8 Nm (6 ft lbs.).