Descrizione
A fan motor on a 700 to 2000 tonne class excavator is not the same component duty as one on a 20 tonne machine. The cooling pack is larger, the oil heat load is continuous, and the machine is expected to run through a shift without a break. Komatsu’s catalogue item name is Motor Assembly and the published width is 328 mm.
Applicabilità
Trade and dealer parts data attach 708-7W-00130 to the Komatsu PC800-8 family, PC850-8, PC1250-8 and PC2000-8 mining excavators. Komatsu’s own catalogue page we can check confirms the item name and dimension but not the machine list, so treat the model coverage as trade-established and confirm against your parts book and machine serial before ordering.
Heat load, in practice
On these machines the fan is hydraulically driven and its speed follows cooling demand, so the motor spends its life cycling between part load and full load against a core face that is constantly collecting blast dust and fines. Two consequences for anyone ordering a replacement:
- A motor removed from a machine that ran hot has almost certainly been working at maximum command for weeks. Inspect the core pack and the oil cooler as part of the job, not afterwards.
- Oil condition decides the life of the replacement. These circuits hold hundreds of litres, and a flush is cheap compared with a second motor and a lost shift.
Test before ordering: flow and pressure at the motor ports, case drain volume with the fan commanded to full, and the routing of the drain line. The sequence is in our guida alla diagnosi del motore ventilatore idraulico.
Montaggio
Match shaft, flange, port orientation and the case drain arrangement against the removed unit. Flush and change filter elements, prime the casing before cranking, keep the drain unrestricted, and target ISO 4406 18/16/13 or better for the piston components in the circuit. Prove full fan speed under load and record temperatures before the machine returns to the pit.
Ordinazione
Minimum order one piece. Three to six month warranty on new aftermarket units as stated on your proforma invoice. Bench checked, photographed against your order before the wooden case closes, delivery 5 to 8 working days from payment subject to stock. The HM400-3 unit in the same 708-7W family is 708-7W-00230; la gamma si trova sotto Motore idraulico del ventilatore Komatsu.
