Valmet (Komatsu forest) Wheeled harvesters ( -2011)

Coolant capacity & service interval

Valmet (Komatsu forest) Wheeled harvesters (-2011) use coolant with a capacity range of 4 to 35 liters. Service intervals include changes at 12 months and 24 months. The data covers 4 configurations.

The configuration chart below lists fill volumes and service intervals for each engine and trim variant.

TypeSpecifications
901.1, >311191
  • Use: Normal
  • Capacity 5 liter
  • Change 12 months
911.1, >311371
  • Use: Normal
  • Capacity 5 liter
  • Change 12 months
921
  • Use: Normal
  • Capacity 4-35 liter
  • Change 12 months
931.1
  • Use: Normal
  • Capacity 35 liter
  • Change 24 months

Additional Notes

  • The Valmet (Komatsu Forest) 901.1 (serial number above 311191) and 911.1 (serial number above 311371) wheeled harvesters share an identical cooling system capacity of 5 liters, paired with a 12-month change interval under normal use conditions.
  • Serial number thresholds on the 901.1 and 911.1 indicate that the listed 5-liter capacity and 12-month interval apply only to units produced from those specific serial numbers onward, distinguishing them from earlier production variants.
  • The 921 model carries a notably wide capacity range of 4 to 35 liters for the cooling system. A range of this breadth typically reflects multiple engine or configuration variants within the same model designation, where smaller figures represent partial or component fills and the upper figure represents a full system capacity.
  • Despite the wide capacity range on the 921, the change interval remains fixed at 12 months under normal use, consistent with the 901.1 and 911.1 specifications.
  • The 931.1 stands apart with a cooling system capacity of 35 liters, the largest single fixed value across all four models listed. A capacity at this level is characteristic of larger-displacement or higher-output engines requiring greater thermal management volume.
  • The 931.1 also carries a 24-month coolant change interval under normal use, which is double the 12-month interval specified for the 901.1, 911.1, and 921. A longer drain interval at this level is generally associated with extended-life coolant formulations designed to maintain corrosion inhibitor effectiveness over a greater service period.

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