Deskripsi
On a 374F there is more than one small variable pump bolted into the hydraulic stack, and that is exactly why a number like 448-9705 gets sold three different ways on the internet. This page sets out what Caterpillar’s own data supports and what it does not.
What Caterpillar states
448-9705 is listed as an Axial Piston Pump, with the parts book item name PUMP GP-PISTON. Cat’s applicability data attaches it to the 374F L with the C15 engine, at prefixes EBF, XWL, MFL, DNM, AP4, AT2 and NFJ, and to the 390F L, 390F and 390F mobile hydraulic power unit with the C18, at FEH, HNG, YHT, MGF, HSM, TYE, GAY, HJD, PT7 and B37, plus the MH3295 material handler. Whether it is variable or fixed displacement is not stated for this number, so we do not claim either.
The pump stack on a 374F, and where this unit sits
The F-series large excavators run a main pump arrangement with secondary units mounted alongside it, and those secondary units do different jobs that all end in the same direction: they supply oil to something that has to spin. On this platform the fan itself is turned by a suction fan piston motor, Cat number 364-0983, listed on its own page here: 364-0983 suction fan piston motor. The pump that feeds that circuit is a separate item.
Some supplier listings place 448-9705 on completely different machines, including 320 GC and 930M models with C4.4 and C7.1 engines, and label it with a different Cat item name. That contradicts Caterpillar’s own applicability data for the C15 and C18 machines quoted above, and we do not repeat it. If you are holding a quotation that names a 320 GC for this number, that is the moment to check the parts book.
Machine context
The 374F L is a machine of about 71,160 kg operating weight with a Cat C15 producing 352 kW (472 hp) net, main system flow up to 952 L/min and a cooling system holding 74 litre. The 390F L is roughly 86,840 kg with a C18 producing 391 kW (524 hp) net to ISO 9249, main system flow of 952 L/min and the same 74 litre cooling capacity. Caterpillar describes the 374F cooling package as a side-by-side system with easy-to-clean cores and a variable-speed fan that can reverse to blow out accumulated debris, with the reversing fan appearing in the standard equipment list.
Two things follow for anyone buying hydraulic parts for these machines. A reversing fan duty means the motor sees its port roles swap, which a single-rotation unit will not survive. And a side-by-side core pack on a quarry machine is a permanent heat-load problem unless it is cleaned, so airflow complaints should start at the core face and finish at the pump.
Diagnosis order for a heat complaint
- Clean the cores and re-measure. On this layout that alone resolves a surprising share of complaints.
- Read the monitor. The F-series controller logs fan circuit and high hydraulic oil temperature events, and that record tells you where to start.
- Command reverse manually. Forward-only operation points at the shift command rather than the hydraulics.
- Measure flow at the motor ports and drain flow from the motor. Correct inlet flow with heavy drain is internal wear in the motor; short inlet flow is the pump or its control.
- Only then order a pump. The test sequence is in our hydraulic fan pump diagnosis guide dan fan motor diagnosis guide.
Fitting
Photograph the hose routing before stripping anything, since port identity matters where a circuit reverses. Match shaft, pilot, flange and control orientation against the removed pump. Prime the casing with clean oil before cranking. Fit a new return filter element and clear the suction strainer, holding cleanliness around ISO 4406 18/16/13 in line with Bosch Rexroth guidance for axial piston units. Keep the case drain unrestricted to tank. Then prove forward speed, reverse function and both temperature readings.
Terms
Minimum order one piece. New aftermarket units carry a three to six month warranty as stated on your proforma invoice. Bench tested, photographed against your order before packing, wooden case, delivery 5 to 8 working days from payment subject to stock. Send the machine serial prefix and we will confirm the number before invoicing. The rest of the CAT range is under Caterpillar hydraulic fan motor.
