Caterpillar — Alternator Belt - Inspect/Adjust/Replace
Maintenance
From a Caterpillar owner's manual covering: C3.3, C3.3 Rental Generator Set, C4.4, C4.4 Rental Generator Set, D4D1-Up, GLE1-Up, N3X1-UP, N4R1-Up, N4X1-Up, X3B1-UP, XYC1-Up, XYD1-Up. Check it applies to your exact model before use.
Applies to: Caterpillar C3.3, Caterpillar C4.4
Before you start
- Replace belts in matched sets for multiple drive belts
Procedure
- Inspect the belts for wear and for cracking. Replace belts that are worn or damaged.
- Install gauge (1) at center of belt between alternator and crankshaft pulley.
- Check tension: new belt 400 N (90 lb) to 489 N (110 lb).
- Used belt (30 minutes or more at rated speed): 267 N (60 lb) to 356 N (80 lb).
- If twin belts are installed, check and adjust tension on both belts.
- Loosen mounting bolts (2) and adjusting bolt (1).
- Move alternator to increase or decrease belt tension.
- Tighten adjusting bolt (1). Tighten mounting bolts (2) to specified torque.
Tools required
- 144-0235 Belt Tension Gauge Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- New belt 400 N (90 lb) to 489 N (110 lb)
- Used belt 267 N (60 lb) to 356 N (80 lb)
Full service-parts list: Caterpillar C3.3 →, Caterpillar C4.4 →
Source: Caterpillar owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.