B4000 SE Cab Plus 4 4WD V6-4.0L OHV (2000)
Drive Belt Tensioner: Testing and Inspection
BELT TENSIONER INSPECTION
The automatic belt tensioner can be checked as follows:
1. With the engine running, observe belt tensioner movement.
2. The belt tensioner should move (respond) when the A/C clutch cycles or when the engine is accelerated rapidly. If the belt tensioner movement is
constant without A/C clutch cycling or acceleration, a pulley or shaft is probably bent or a pulley is out of round. In rare cases, excessive drive belt
rideout (uneven depth of grooves in drive belt) can cause excessive belt tensioner movement. This condition can be checked by replacing the
suspect drive belt with a known good original equipment drive belt and repeating the observation.
