Описание
Komatsu’s catalogue entry for 708-7W-00230 gives the item name Motor Assembly and a published width of 328 mm, which places it in the same large fan motor family as the 708-7W-00130 used on the PC800 and PC1250 excavators. The machine list below is where we have to be careful, and we would rather flag it than pad it.
Applicability, and what is not confirmed
Our incoming parts sheet lists the Komatsu HM400-3 articulated hauler for this number, and independent dealer and salvage inventory records describe the HM400-3 cooling fan as a hydraulic drive, which is consistent. What we could not find is a Komatsu catalogue page that states the machine coverage for 708-7W-00230 directly. So: HM400-3 is published here as the primary application on trade and dealer evidence, listings that also attach the number to HM400 and HM400-5 are treated as unconfirmed, and the machine serial prefix decides.
Why an articulated hauler is hard on a fan motor
A hauler works a cycle of loaded climb and empty return, with the engine under sustained load on the haul road and the hydraulics cycling constantly. Cooling demand therefore swings hard and often, and the fan motor is asked to follow it thousands of times a day. Add a haul road dust load that the core sees in its worst form and the picture is clear: on these machines, airflow loss is normal service life, not a fault.
Before condemning a motor on an HM400-3:
- Clean the cores and re-measure temperatures on a loaded cycle.
- Confirm the fan reaches full speed when the controller asks for it.
- Measure flow at the motor ports; short supply is the pump or its command.
- Check case drain volume for internal bypass, and the drain hose routing for restriction.
Procedures are in our hydraulic fan motor diagnosis guide и the oil overheat check valve article.
Установка
Match shaft, flange, port orientation and drain arrangement against the removed unit. Flush and change filter elements, prime the casing before cranking, keep the case drain unrestricted, and target ISO 4406 18/16/13. Prove full fan speed under load before the machine returns to the haul road.
Заказ
Send the number cast on your motor and the machine serial prefix. Minimum order one piece, three to six month warranty on new aftermarket units as stated on your proforma invoice, bench checked and photographed before the wooden case closes, delivery 5 to 8 working days from payment subject to stock. The excavator unit in the same family is 708-7W-00130; the range sits under Komatsu hydraulic fan motor.
