10-21-2025, 05:49 PM
CAT Fuel Pump 326-4635 and Its Application
The Caterpillar fuel pump with part number 326-4635 is commonly found on mid-range diesel engines used in agricultural, construction, and industrial equipment. It is often paired with Perkins CR200-series engines, particularly in the 1100 series. This pump integrates a fuel shutoff solenoid mounted on top, which controls fuel delivery during engine start and stop cycles. The solenoid is a critical component, and when it fails—especially by leaking diesel through the electrical connector—it can cause hard starting or complete engine shutdown.
Terminology Note
The solenoid valve on top of the 326-4635 pump is marked with part number 312-5620, which is a valid identifier but not listed for individual sale in Caterpillar’s system. This part is designated as NSS, meaning it is only available as part of the complete pump assembly. This policy is common for components that are factory-calibrated or considered integral to the pump’s performance.
Attempts to locate the solenoid through CAT’s SIS (Service Information System) often lead to part number 248-1064, which is also marked as unavailable. Another listing, 286-1511, appears as a fuel shutoff solenoid but is flagged as an indirect replacement, requiring dealer confirmation. These inconsistencies make sourcing the solenoid a challenge for technicians and fleet managers.
Alternative Sourcing Strategies
In the UK, an agri-technician encountered a leaking solenoid on a CAT pump and was unable to source the part through official channels. After contacting a Perkins dealer and providing the engine model, he was able to locate a compatible solenoid used on a similar 1100 series engine. The replacement worked without issue and cost significantly less than a full pump.
In Brazil, a technician noted that the solenoid was a simple on/off valve and did not require timing or calibration. He sourced a generic unit from a local supplier and installed it successfully, restoring engine function.
Recommendations for Maintenance and Replacement
The solenoid valve on CAT fuel pump 326-4635 is a known failure point but is not sold separately by Caterpillar. While part numbers like 312-5620 and 248-1064 exist, they are often flagged as NSS or indirect replacements. Technicians must rely on Perkins dealers, fuel pump rebuilders, or aftermarket suppliers to source compatible solenoids. With careful matching and installation, the issue can be resolved without replacing the entire pump, saving time and cost.
The Caterpillar fuel pump with part number 326-4635 is commonly found on mid-range diesel engines used in agricultural, construction, and industrial equipment. It is often paired with Perkins CR200-series engines, particularly in the 1100 series. This pump integrates a fuel shutoff solenoid mounted on top, which controls fuel delivery during engine start and stop cycles. The solenoid is a critical component, and when it fails—especially by leaking diesel through the electrical connector—it can cause hard starting or complete engine shutdown.
Terminology Note
- Solenoid Valve Assembly: An electromechanical device that opens or closes fuel flow based on electrical signals.
- NSS (Not Sold Separately): A designation used by manufacturers indicating that a component is not available as an individual part.
- Indirect Replacement: A part that is not directly listed but may be substituted with dealer assistance.
The solenoid valve on top of the 326-4635 pump is marked with part number 312-5620, which is a valid identifier but not listed for individual sale in Caterpillar’s system. This part is designated as NSS, meaning it is only available as part of the complete pump assembly. This policy is common for components that are factory-calibrated or considered integral to the pump’s performance.
Attempts to locate the solenoid through CAT’s SIS (Service Information System) often lead to part number 248-1064, which is also marked as unavailable. Another listing, 286-1511, appears as a fuel shutoff solenoid but is flagged as an indirect replacement, requiring dealer confirmation. These inconsistencies make sourcing the solenoid a challenge for technicians and fleet managers.
Alternative Sourcing Strategies
- Contact Perkins Dealers: Since the pump is shared with Perkins CR200 applications, some Perkins dealers may stock or recognize the solenoid as a serviceable item.
- Fuel Pump Rebuilders: Independent diesel shops may have access to aftermarket or salvaged solenoids and can rebuild the pump without replacing the entire unit.
- Parts Cross-Reference: Use the solenoid’s physical dimensions and connector type to match it with generic fuel shutoff solenoids from other manufacturers.
- Aftermarket Suppliers: Some vendors offer compatible solenoids that do not require factory calibration, especially for non-emissions-critical applications.
In the UK, an agri-technician encountered a leaking solenoid on a CAT pump and was unable to source the part through official channels. After contacting a Perkins dealer and providing the engine model, he was able to locate a compatible solenoid used on a similar 1100 series engine. The replacement worked without issue and cost significantly less than a full pump.
In Brazil, a technician noted that the solenoid was a simple on/off valve and did not require timing or calibration. He sourced a generic unit from a local supplier and installed it successfully, restoring engine function.
Recommendations for Maintenance and Replacement
- Inspect the solenoid for leaks during routine service, especially around the electrical connector.
- If diesel is present inside the connector, replace the solenoid or pump immediately to prevent electrical shorts.
- Keep a record of pump and solenoid part numbers, including casting marks and connector types.
- When replacing the pump, verify that the new unit includes a compatible solenoid and matches the engine’s fuel map.
The solenoid valve on CAT fuel pump 326-4635 is a known failure point but is not sold separately by Caterpillar. While part numbers like 312-5620 and 248-1064 exist, they are often flagged as NSS or indirect replacements. Technicians must rely on Perkins dealers, fuel pump rebuilders, or aftermarket suppliers to source compatible solenoids. With careful matching and installation, the issue can be resolved without replacing the entire pump, saving time and cost.
