125-5774 Caterpillar 24V Fuel Shutoff / Shutdown Solenoid: Its primary function is to control the engine's fuel path, enabling fuel supply for starting and fuel cutoff for shutting down.

I. Key Specifications

Model: 125-5774 (1255774)

Type: Pull-Type Fuel Shutoff Solenoid

Voltage: 24V DC

Mounting: Flange mount; hole spacing: 2.50 inches (63.5 mm)

Operating Temperature: -40°C to +121°C

Function: Energized (Engaged) → Opens fuel path (Engine running); De-energized (Released) → Cuts off fuel path (Engine shut down)

II. Compatible Engines and Equipment Models

Compatible Engines

3204, 3304, 3304B, 3306, 3306B, 3306C, 3406B, 3406C

Compatible Equipment (Partial List)

Loaders: R1300, R1300G (Underground Mining)

Cold Planers: PM-465

Pavement Reclaimers: RM-250C, RM-350, RM-350B, RR-250, RR-250B

Generator Sets: SR4, SR4B, and various industrial/marine generator sets

III. Replacement Models and Pricing

Replacement Models: 6T-4121, 6T-4122, CA1255774

IV. Common Faults and Troubleshooting

Failure to Start: Solenoid fails to engage → Check 24V power supply, electrical connector, and coil resistance (normally approx. 20–30Ω).

Failure to Shut Down: Solenoid fails to release → Check power-off signal, check for spool binding/sticking, and check the return spring.

Installation Notes: Mount on the fuel injection pump or fuel line; ensure the spool completes its full stroke travel and that the seal is leak-free.