説明
Komatsu’s catalogue calls this part Motor Assembly and files it under hydraulics. Trade applicability puts it on the D61, D65 and D85 -15 generation dozers in the cooling fan position, and that pairing is consistent with how Komatsu numbers the circuit: on these machines the fan pump is a 708-1S item and the fan motor is the matching 708-7S item.
適用性
Komatsu D61EX, D61PX, D65EX, D65PX, D65WX, D85EX, D85MS and D85PX. The -15 series designation matters as much as the model letters, because Komatsu changed the cooling package between generations and a D65EX of a different series will not necessarily take this motor. Confirm from the number cast on your housing and the machine serial prefix.
The pair on a -15 dozer
A dozer cooling circuit has two serviceable hydraulic parts, and on this generation they are catalogued as a set of siblings: the 708-1S fan pump meters the oil, and the 708-7S motor on this page turns the fan. When a D65 runs hot, both are suspects, and the difference shows up in a flow test rather than in the temperature gauge.
On a job site the pattern is usually one of three. The motor has worn internally, so flow arrives and the fan still lags while the hydraulic oil heats up. The pump has lost displacement, so the fan never receives enough volume and the oil temperature stays closer to normal. Or neither is at fault and the core pack is plugged with clay, which on a dozer working a fill site is the most common answer of the three. Clean the cores first, always, and re-measure before spending money.
Tests to run
- Fan speed at high idle with warm hydraulic oil, compared against a cool machine.
- Flow and pressure at the motor ports. Short supply points at the pump.
- Case drain volume with the fan commanded to full. A heavy drain stream means internal bypass in this motor.
- Case drain line routing. Back-pressure in the casing is what finishes shaft seals, and dozer service access makes it easy to trap the hose.
The procedures are written up in our hydraulic fan motor diagnosis guide および ファンポンプ診断ガイド.
取付け
Match shaft form, flange and port orientation against the removed motor. Flush the circuit and change the return filter element if the old unit produced debris. Prime the casing with clean oil before the first crank. Keep the case drain unrestricted to tank. Target cleanliness around ISO 4406 18/16/13 for the piston components in the circuit. Confirm rotation with the fan restrained, then prove full fan speed under load and record coolant and hydraulic oil temperature.
ご注文
Minimum order one piece. New aftermarket units carry a three to six month warranty 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, by sea, air or express courier. The wheel loader fan motors on this page’s sibling listings are 708-7S-00550, and the range sits under コマツ油圧ファンモーター.
