Komatsu Camshaft for 6D95, 6D125, 6D155 Engines | Excavator Applications

Technical Q&A: Komatsu Camshafts

Why did my Komatsu PC200 camshaft fail (lobe spalling)?

Symptom: Loud mechanical ticking from the valve cover, progressive loss of engine power, and poor exhaust gas circulation. Diagnosis: High-hour wear combined with low-lubricity engine oil disrupts the boundary lubrication film between the cam lobes and roller lifters, leading to severe metal-to-metal friction and spalling (pitting) on the lobe nose. Solution: Replace the worn camshaft with a high-nickel chilled cast iron camshaft having a lobe surface hardness of HRC 52-58, and always install new roller followers during the overhaul.

Are Komatsu 6D95 and 6D102 camshafts interchangeable?

Symptom: Misfiring, excessive exhaust smoke, and potential valve-to-piston contact upon starting a mismatched rebuild. Diagnosis: Although both are inline-6 engines of similar sizes, the 6D95 and 6D102 feature completely distinct valve lift profiles, duration angles, and timing gear lash setups. Solution: These camshafts are not interchangeable. Always verify compatibility using the exact part number (e.g., 6207-41-1111 for 6D95 vs. 6735-41-1111 for 6D102) to match your engine block block serial number.

What causes the timing gear keyway to shear on Komatsu camshafts?

Symptom: Engine sudden shutdown, complete loss of valve timing coordination, and severe internal valve train damage. Diagnosis: Torsional harmonic vibrations caused by an unbalanced crankshaft or timing gear misalignment put extreme shear stress on the camshaft keyway under heavy load. Solution: Replace the sheared unit with a 100% dynamically balanced camshaft and check timing gear backlash (standard: 0.030 to 0.120 mm) along with crankshaft damper integrity before starting the engine.

What are your wholesale terms for Komatsu engine parts?

Symptom: Sourcing delays, uncompetitive pricing, or unreliable quality from middle-man distributors. Diagnosis: High-volume fleet overhauls and equipment rental managers require direct factory-level supply lines to control costs and lead times. Solution: We provide flexible trade terms (T/T, L/C payment options) and short lead times (15 to 30 days) on bulk orders. Our manufacturing is ISO 9001 certified, ensuring consistent, heavy-duty metallurgical reliability for global parts distributors.