GEAR-SUN 2136190 - Caterpillar

Installation
Illustration 1, Side view of belt tightener showing placement of 132-1123 Decal (A) on spring case (D) between parting line and pivot arm. Heavy black line (B) of decal. Shoulder of pivot arm used as pointer indicator (1). Initial red zone (2). Green operating range (3). Red zone (4). Beginning of overtravel zone (C).
Illustration 2, Side view of belt tightener showing movement of pointer indicator after tightening the belt. Heavy black line on decal (B) has moved in relationship to shoulder of pivot arm used as pointer indicator (1). Pointer indicator (1) is now in the green operating range (3).Remove the belt and allow the tightener to come to rest on the free arm stop (6).
Removing the tightener is not necessary but may be easier. Prepare the spring housing surface to accept the decal by removing all loose paint, grease, oil and dirt. Remove the masking on the face of the decal and the backing. Apply the decal to the case of the tightener by aligning the heavy black line on the decal (B) to the shoulder of the tightener arm on the right hand (outboard) side of the tightener.
When checking the decal for the correct position, always have the engine OFF.
Illustration 3, typical view of alternator group, spring tang (5), free arm stop (6).When changing to a new belt, swing the alternator (inboard) to the initial part of the slot. Run the engine for five minutes to allow for initial belt stretch and seating in the grooves. Adjust the indicator to the far edge of the green zone (overtravel area) (C). Make sure that the back of the belt does not hit the spring tang (5).
When making an adjustment, always adjust as close to the overtravel zone (C) as possible without rubbing the belt on the spring tang (5). This will allow for the most time between adjustments.