Beschreibung
Komatsu’s catalogue names this part Pump Assembly and files it in the same hydraulics group as the fan motors, and the trade applies it consistently to the cooling fan on the -15 generation dozers. Within Komatsu’s 708 numbering, the 1x series carries the pumps and the 7x series the motors, which is why 708-1S-00241 and 708-7S-00352 appear as a pair on the same machine.
Anwendbarkeit
Komatsu D61EX, D61PX, D65EX, D65PX, D65WX, D85EX, D85MS and D85PX of the -15 series. Komatsu publishes no displacement, pressure or flow figure for this number, so none is quoted here; if you are matching against a data sheet, the number on your housing and the machine serial prefix are the reliable references.
What this pump actually does on a dozer
A dozer’s cooling demand is unusual: long low-speed cycles with the converter loaded, enormous dust, and a fan that has to pull air through a radiator, an oil cooler and an aftercooler stacked behind one grille. The fan pump converts engine rotation into oil flow for the fan motor, and on this generation its output is governed by cooling demand rather than engine speed. When it wears, the fan stops reaching full speed exactly when the machine needs it most, which is at the end of a push cycle on a hot day.
Pump or motor: the test that decides the order
- Clean the cores first and re-measure. On a dozer this resolves a large share of heat complaints with no parts at all.
- Measure flow and pressure at the pump output with the oil hot. Short output points here.
- Correct output with a fan that still lags and a heavy case drain at the motor points at the motor instead.
- No command signal arriving is a third possibility, and a new pump will not fix it.
The full procedures are in our Diagnoseleitfaden für hydraulische Lüfterpumpen und Leitfaden zur Diagnose von Lüftermotoren.
Montage
Match shaft spline, pilot diameter, flange, port positions and the control orientation against the removed pump. Prime the casing with clean oil before cranking. Change the return filter element and clear the suction strainer, targeting ISO 4406 18/16/13. Keep the case drain unrestricted to tank. Then prove the fan reaches full speed under load and record coolant and hydraulic oil temperature.
Bestellung
Minimum order one piece. Three to six month warranty on new aftermarket units as stated on your proforma invoice. Bench checked and photographed against your order before the wooden case closes, delivery 5 to 8 working days from payment subject to stock. The range sits under Komatsu Hydraulik-Lüftermotor.
