COVER-SEAT 2337530 - Caterpillar

Preparation (Rear Pump)
Pump Compartment
(9) Hose (rear pump charge line). (12) Plug (rear pump delivery line). (15) Rear pump. (25) Tap (rear pump). (33) Negative flow control line.Perform the same preparation as that described for the front pump flow test under constant horsepower control except Step 3. Use the following procedure in replacement for Step 3, for the rear pump (15).a. Disconnect delivery hose (17) from rear pump (15).b. Install plug (12) and seal (11) to the end of delivery hose (17).c. Disconnect return line (18) from swing motor (19).d. Install tee (13) and two seals (11) to the swing motor (19) return port. Connect return line (18) to tee (13).e. Connect flow meter (1) between rear pump (15) and return line (18).f. Install pressure gauge (22) at rear pump tap (25). [A 49 000 kPa (7100 psi) pressure gauge can be used in place of pressure gauge (22).] Tap (25) is used to measure the rear pump delivery pressure.g. Install multitach group (32) on engine (31). This is used to read engine speed.h. Disconnect negative flow control line (33) from rear pump (15) and install plug (29).i. Install test hose (28) to rear pump negative flow control port.j. Install tee (27) and pressure gauge (30) on pilot oil manifold tap (26). Connect test hose (28) to tee (27).Test Procedure
Perform the front and rear pump negative flow control tests one at a time.
To prevent personal injury or equipment damage from failure of the flow meter or associated circuit components because of blocked pump flow, make sure before starting the engine that the flow meter valve (27) is fully open (turned counterclockwise).
To prevent personal injury and/or equipment damage from failed lines or components while the flow meter is returned to the open flow position after a flow test, slowly open the flow meter valve and monitor pump flow at the same time to make sure flow increases. If pump flow does not increase as the flow meter is opened, shut the engine off and determine what is causing the pump not to upstroke.
1. Slowly turn valve (34) of portable hydraulic tester (1) clockwise until the pump delivery pressure setting is 6900 kPa (1000 psi).2. Adjust pilot relief valve (35) of pilot oil manifold (24) until pressure gauge (30) connected to tee (27) reads 2350 kPa (340 psi).3. Record the negative control flow at each of the following pressure points. Flow specifications given above are based on an engine speed of 1800 rpm. To get more accurate test results, measured flow should be corrected by calculating as follows: Flow corrected for 312 Excavator = (Flow measured × 1900) ÷ rpm measuredFlow corrected for 311 Excavator = (Flow measured × 1800) ÷ rpm measured
P-Q Characteristic Curve [Negative Flow Control at 6900 kPa (1000 psi) Pump Delivery Pressure]Pump Flow Adjustment
Flow Adjustment Under Constant Horsepower Control
Main Pump
(1) Setscrew. (2) Locknut. (3) Setscrew. (4) Locknut. (5) Locknut. (6) Setscrew. (7) Setscrew. (8) Setscrew. (9) Setscrew.Flow adjustment procedure for the front and rear pumps under constant