MOTOR TRUCK SERVICE LETTER #SL 51
September 24, 1958
Subject File — Engine
Fan Belt Slippage Overcome by Use of Cog Type Fan Belt. A-100 Through A-160 and Metro Chassis Equipped With 35 AMP Charge at idle Generators.
A cog type fan belt is now being utilized on A—Line and Metro model vehicles
equipped with 35 AMP charge at idle generators.
Use of this type fan belt was required after reports had indicated that fan belt
slippage was being experienced on vehicles used in stop and start operations,
thus resulting in run down batteries.
Where fan belt slippage is being experienced on chassis in service equipped I
with 35 AMP charge at idle generators, the new cog type fan belt should be installed.
FAN BELT ADJUSTMENT:
The tension of the fan belt should be checked periodically. Proper tension is
obtained when the belt can be depressed approximately l/2. inch halfway between the fan pulley and generator. To adjust the belt, loosen the generator mounting cap screws and the generator brace cap screw. After the adjustment be sure to tighten the cap screws.
Part numbers involved in the above change are as follows:
New Part Replaced Part No., Description, Replace Part No., N0. Req’d.
81 572-R2, Fan Belt (Cog Type), 81 572-R1, 1