Beschreibung
The D51-22 is a small dozer doing large-dozer work: landscaping, utility trenching and finish grading, where the machine idles under hydraulic load for long stretches with almost no ram airflow. That duty cycle is why fan drive components fail on light dozers more often than the size of the machine suggests.
Anwendbarkeit und Nachweis
EPC-derived parts data lists this fan pump for the Komatsu D51EX-22 and D51PX-22, with 708-1T-00541 recorded as the neighbouring catalogue item for the same application. Komatsu’s own online catalogue does not return an entry we can cite for either number, so the item name is not manufacturer-confirmed here, and no supersession relationship between the two is documented. We ship against the number cast on your old pump and the machine serial prefix.
Why idle-heavy duty is hard on a fan pump
- At low engine speed the pump turns slowly, so it must run near maximum displacement to hold airflow, which is where wear accumulates fastest.
- Long idling with the machine hot keeps the oil at temperature for hours without the cooling benefit of vehicle speed.
- Finish work kicks fine dust straight into the core face, and a small dozer’s cooler pack has less margin to spare.
So the sequence is: clean the cores, check the oil level and the return filter, then measure pump output pressure and flow at working temperature. If output is short, the pump is the answer. If output is correct but the fan still lags, look at the motor and its case drain. Our Diagnoseleitfaden für hydraulische Lüfterpumpen und Leitfaden zur Diagnose von Lüftermotoren cover both.
Montage
Match shaft spline, pilot, flange, port positions and 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. Prove full fan speed at low idle, which is the condition that matters most on this class of machine.
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 D155-6 fan pump is 708-1T-00472; die Reihe befindet sich unter Komatsu Hydraulik-Lüftermotor.
