DRIVE GP-FAN 9N0793 - Caterpillar

COMPONENTS OF THE TRANSMISSION LINKAGE
4. Valve group for automatic selection of speed. 9. Hydraulic shift spool. 11. Manual selection spool. 39. Selection valve body. 46. Selection spools (four). 63. Manual selection cam. 64. Hydraulic shift cam.Adjustment Of Shift Points
The screws for shift adjustment are inside the transmission case behind plugs (65), (66), (67) and (68). Screw (DD) behind plug (65) changes all downshift points and supply oil to the governor. One clockwise turn of screw (DD) makes downshift points go DOWN approximately 20 engine rpm.Screw (AA) behind plug (66) changes the 2nd to 3rd speed upshift point. Screw (CC) behind plug (67) changes the 3rd to 4th, 5th to 6th and 7th to 8th speed upshift points. Screw (BB) behind plug (68) changes the 4th to 5th and 6th to 7th speed upshift points. One clockwise turn of screws (AA), (BB) and (CC) make the upshift points of that specific speed change (see SHIFT POINT CHART) go UP approximately 15 engine rpm.
REFERENCE PRESSURE LOCATION OF ADJUSTMENT SCREWS
65. Plug for access hole to screw (DD) (adjustment on pressure reducing valve for all downshift points). 66. Plug for access hole to screw (AA) (adjustment of reference pressure of upshift point for 2nd to 3rd speed). 67. Plug for access hole to screw (CC) (adjustment of reference pressure of upshift points for speeds 3rd to 4th, 5th to 6th and 7th to 8th). 68. Plug for access hole to screw (BB) (adjustment of reference pressure of upshift points for speeds 4th to 5th and 6th to 7th).1. Start the engine and let the transmission oil get to normal temperature of operation.2. Put the transmission selector lever, at the operator's console, in 2nd speed position and run engine at 1500 rpm.3. Check the supply oil to the governor at test location (D). Pressure must be approximately 96 psi (660 kPa).4. If supply pressure for governor is not correct, turn adjustment screw (DD) to get correct pressure. Oil supply pressure for governor is changed when adjustment is made to downshift points.
LOCATION OF PRESSURE TAPS FOR THE GOVERNOR
A. Governor shift pressure (2nd through 4th speeds). B. Governor shift pressure (4th through 6th speeds). C. Governor shift pressure (6th through 8th speeds). D. Supply pressure for governor.5. Put the transmission selector lever in 3rd speed position and make the engine rpm go up to get a 2nd to 3rd speed upshift.6. Put the transmission selector lever in 4th speed position and run engine at 1900 rpm.7. Slowly make the engine rpm go up and turn screw (CC), as necessary, to get a 3rd to 4th speed upshift when the engine is running at 2130 30 rpm.8. Slowly make the engine rpm go down and turn screw (DD), as necessary, to get a 4th to 3rd speed downshift when the engine is running at 1495 30 rpm.9. Slowly make the engine rpm go down and turn screw (DD), as necessary, to get a 3rd to 2nd speed downshift when the engine is running at