Mô tả
Caterpillar puts a displacement figure in the title of this part, which is unusual and useful: 74Cc. On a motor grader that number matters more than on most machines, because the steering pump is what keeps the articulation and centreshift moving while the implement pump is doing blade work.
Applicability
Verified in Cat’s parts literature: 140H from prefix XZH 00001 on the 3306, 120H at 9YR from 00001 on the 3116, and 120H at 6TM 00001 to 00442. Supplier applicability extends the same pump to 12H, 135H, 160H and the K-series 12K, 120K, 140K and 160K. Those are consistent with Cat’s serial data but were not individually booked in the pages we checked, so treat the H family as confirmed and the K family as confirm by PIN.
Two pumps in one stack, and one rotating group name that misleads
The grader runs a tandem pair: 6E-3136 is the steering pump 以及 6E-3137 is the implement pump, bolted together behind a shared bell housing. They are siblings, not substitutes, and their reman numbers differ too: 0R-7682 for this pump, 0R-7672 for the other.
One detail in Cat’s own parts list trips up buyers. The steering pump’s rotating group is catalogued with a name that includes hydraulic oil cooling and radiator cooling. That is Cat’s part-name convention for that group, reused on other pumps in the range. It is not a statement that 6E-3136 is a fan pump, and several supplier pages have made exactly that mistake.
What Cat publishes about the grader cooling circuit
For the current Cat 140, the specification lists a hydraulic demand fan that adjusts automatically to engine cooling requirements, a variable piston pump with 210 L/min output at 2,150 rpm, maximum system pressure of 24,150 kPa with a 3,100 kPa standby pressure, and load-sensing electro-hydraulics. Those figures belong to the current machine, not the 140H, and we do not apply them to this part. They do explain why a grader that steers slowly when the blade is loaded is usually a pump priority problem rather than a steering valve problem.
Failure signs
- Hard or slow articulation, especially with the blade loaded: steering pump wear or a compensator set wrong.
- Noise at idle that disappears with rpm: cavitation. Check the suction line and tank filter.
- Oil at the shaft: case drain back-pressure or a worn coupling.
The test sequence is in our pump diagnosis guide and the comparison method in the pump buyer’s and specification guide.
Fitting and ordering
Match shaft spline, pilot, flange, port positions and the compensator setting against the removed pump, and confirm rotation direction. Prime the casing before cranking, change the filter element, keep the case drain unrestricted, and target ISO 4406 18/16/13. Minimum order one piece, three to six month warranty as stated on your proforma invoice, bench tested and photographed before packing, delivery 5 to 8 working days from payment subject to stock. The range sits under CAT hydraulic pump.
