Caterpillar — Generator Bearing - Inspect/Replace (SR4 Generator)
Repair & overhaul
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
- DO NOT MIX GREASES
- On two-bearing generators the front bearing can only be removed after the drive coupling is removed
Procedure
- At every major engine overhaul remove the bearing bracket.
- Inspect bracket bore, bearing outer race and rolling elements.
- On standby power units inspect bearing and replace grease at three year intervals.
- Inspect the sleeve for out of roundness, excessive wear and bracket step less than 0.0762 mm (0.0030 inch).
- Clean all ball bearings. Repack the bracket cavity with 2S-3230 Grease (one-third to one-half cavity volume).
- Use an induction heater to heat ball bearings to 107 C (224.6 F) for ten minutes to install.
- Heat the hub to 400 C (752.0 F) for three hours to reinstall the hub on the shaft.
- Remove the bracket drain plug and operate the generator for one hour.
- Stop the engine. Install the bracket drain plug. Wipe off excess grease.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
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.