TM 5-3805-281-24-2
Cooling System
CHECKING BELT TENSIONER SPRING
TENSION AND BELT WEAR
Belt drive systems equipped with automatic (spring) belt
tensioners cannot be adjusted or repaired. The automatic
belt tensioner is designed to maintain proper belt tension
over the life of the belt. If tensioner spring tension is not
within specification, replace tensioner assembly.
CHECKING BELT WEAR
The belt tensioner is designed to operate within the limit
Belt Tensioner
of arm movement provided by the cast stops (A and B)
when correct belt length and geometry is used.
Visually inspect cast stops (A and B) on belt tensioner
assembly.
If the tensioner stop on swing arm (A) is hitting the fixed
stop (B), check mounting brackets (alternator, belt
tensioner, idler pulley, etc.) and the belt length. Replace
belt as needed (see operator's manual).
RG,RG34710,1241
1923OCT971/3
CHECKING TENSIONER SPRING TENSION:
A belt tension gauge will not give an accurate measure of
the belt tension when automatic spring tensioner is used.
Measure tensioner spring tension using a torque wrench
and procedure outlined below:
1. Release tension on belt using a long-handle 1/2-in.
breaker bar in tension arm. Remove belt from pulleys.
2. Release tension on tension arm and remove breaker
bar.
Checking Belt Tensioner
3. Put a mark (A) on swing arm of tensioner as shown.
4. Measure 21 mm (0.83 in.) from (A) and put a mark (B)
on tensioner mounting base.
Continued on next page
RG,RG34710,1241
1923OCT972/3
