Vehicle Compatibility
Alternator rectifier for Delco 10SI and Delco 20SI alternator applications where the alternator uses a matching negative rectifier plate and the same physical dimensions. This unit is specified for 12V systems with a 35A rating and 6 diodes. Commonly referenced in heavy duty and equipment alternator rebuild work, including Caterpillar applications where the OE numbers listed below match. Confirm by alternator series (10SI/20SI), rectifier type (negative), and dimensions before ordering.
- Delco Alternator Series: 10SI; 20SI
- Caterpillar: Applications matching OE 3N3750; 358207; 366744; 377559; 7N122; 7N7122; 9N1203
Specifications
- Reference: RCT2602
- Part Type: Alternator Rectifier
- Rectifier Type: Negative Rectifier
- System Voltage: 12V
- Rated Current: 35A
- Number Of Diodes: 6
- Outer Diameter: 80mm
- Height: 27mm
- Length: 42.6mm
- Width: 81.6mm
- Alternator Series: Delco 10SI / 20SI
OE Numbers
- Caterpillar: 3N3750
- Caterpillar: 358207
- Caterpillar: 366744
- Caterpillar: 377559
- Caterpillar: 7N122
- Caterpillar: 7N7122
- Caterpillar: 9N1203
Features
- Negative rectifier plate design for Delco 10SI and 20SI alternator rebuild applications
- 80mm outer diameter with 6 diode layout to match compatible alternator housings
- 35A rating for stable rectification on 12V systems
- Helps restore charging performance where failed diodes cause low charge, battery drain, or excessive AC ripple
- Common Caterpillar OE coverage where alternator and rectifier specification matches
Why Buy From Us
- Local South African stock with nationwide courier delivery
- 12-month warranty subject to correct application and installation
- Fitment support using alternator labels and clear photos of the existing rectifier and dimensions
- Trusted by workshops and fleet operators for dependable charging system components
Trusted by thousands of South African drivers for quality and durability.
Installation & Maintenance Tips
- Disconnect the battery before alternator removal or rectifier replacement
- Confirm the alternator series is 10SI or 20SI and the rectifier required is the negative rectifier plate
- Inspect stator windings, solder joints and insulation while the alternator is open
- Replace worn brushes and check slip rings during the rebuild to prevent repeat failures
- After installation, verify charging voltage under load and test for abnormal AC ripple
- If you are unsure about alternator repairs, have the unit fitted and tested by a qualified auto electrician
