how to protect hydraulic pump excavator

Quick Answer When a SANY SY500 travels slowly on one side only, the symptom itself is the most useful clue you have: it rules out everything that serves both tracks. The fault must be in one track's circuit or one track's final drive. The decisive test is simple and costs nothing — swap the travel hoses left to right. If the slow side follows the hoses, the problem is hydraulic (relief, cont...

Quick Answer Your CAT 312C needs the SBS80 because that is the pump size matched to a machine of this class. A 12 to 13 tonne excavator has a moderate engine and a moderate flow demand, and the pump has to sit exactly between the two: too large and the engine lugs and burns fuel; too small and the functions starve under load. The SBS80 is the twin axial-piston main pump built for that balance, del...

Quick Answer A CAT 320C or 320D pump loses power under heavy load for one fundamental reason: internal leakage grows as pressure rises. At light load the wear is invisible — the pump simply strokes a little further and the machine feels normal. Put the bucket into hard ground, pressure climbs, more oil escapes past worn plungers and valve plates instead of reaching the actuators, and the mac...

Quick Answer The main pump on a Komatsu PC300-8 or PC350-8 is an HPV140 class unit, ordered under 708-2G numbers. The catch is that the -7 and -8 generations share this pump family and cross-list each other's numbers — in the market, 708-2G-00024 is quoted predominantly against the -7 machines (PC300-7, PC350-7, PC360-7), while 708-2G-00700 and 708-2G-00150 are listed for the -8 machines. On...

Quick Answer Customers buy a TM40 travel assembly for one of two reasons: a travel drive has failed or is failing, or a fleet owner wants to standardise on one drive across machines of several brands. The TM40 is a cross-brand final drive for 18 to 25 tonne excavators — Hyundai R210-7, Doosan DX225, Volvo EC210B, and Chinese machines from Sany, XCMG and LiuGong. It does three jobs: turn hydr...

Quick Answer For a CAT 330GC the travel assembly is ordered under 593-7299, 593-7301, 596-3804, 593-7298, 596-3805 and 593-7300 — six references for one unit that weighs about 351 kg and is also listed for the 330, FM538, 538 and 330MHPU machines. Before you pay, verify two things: on the machine, the number on your old plate and the hole pattern of the mounting flange; and from the supplier...