About this part
108-6633 is supplied as a remanufactured replacement plunger. Cross-reference numbers: 108-6633, CAT3406. Application recorded for this part: Fits Caterpillar — 3406 CAT.
This sits in the injection system where pressures are high and clearances small. Its performance depends on surfaces staying clean and true — a trace of debris or a damaged sealing face is enough to change how the engine runs.
Expect problems to surface as hard starting, unstable idle, visible smoke or rising consumption rather than as one clean, isolated fault.
Confirm the diagnosis before ordering: check supply condition, look for contamination, and compare behaviour across cylinders where applicable.
Assembly notes: keep everything scrupulously clean, renew seals and washers, torque to specification, and prime the system before starting.
Rebuilt rather than refurbished: full teardown and measurement, worn components replaced instead of cleaned and reused, sealing surfaces restored to specification, then bench calibration and testing. The record is what separates this from a used part — we can provide the test sheet for your order. Covered by a 12-month warranty.
Specifications
| Part number | 108-6633 |
| Condition | Remanufactured (not a genuine OEM new part) |
| Cross-reference | 108-6633, CAT3406 |
| Application | Fits Caterpillar — 3406 CAT |
| Process | Disassembled, cleaned, measured, wear parts replaced, machined to specification |
| Bench test | Delivery, return flow, opening pressure and leakage recorded before dispatch |
| Warranty | 12 months |
Fitment note. Several part numbers in this family look similar. Confirm the number on your
existing unit, the engine model and the machine or vehicle application before ordering. Send us a nameplate photo
and we will verify the match before dispatch.
All manufacturer names, symbols and part numbers are used for identification and cross-reference purposes only. We are not an authorised distributor and are not affiliated with the original equipment manufacturer. Products offered are remanufactured or new aftermarket replacement parts unless stated otherwise.
