HOSE AS 2721152 - Caterpillar

Illustration 6 g00682227
Pressure control valve (5) Selector piston plugs (seven) (6) Modulation reduction valves (seven) (7) Load piston orifices (six) (8) Decay orifice plugs (five) (9) Load piston plugs (six) (A) Pressure taps (identification for the load pistons) (B) Pressure taps (identification for the load pistons) (C) Pressure taps (identification for the load pistons) (D) Pressure taps (identification for the load pistons) (E) Pressure taps (identification for the load pistons) (F) Pressure taps (identification for the load pistons) (G) Pressure taps (identification for the load pistons) (H) Pressure taps (identification for the load pistons)Use Illustration 6 for the following problems.Problem: The pressures at all the clutches are 0 kPa (0 psi).
Probable CauseThe probable cause is the pilot pressure. Perform the test in the Power Train Testing and Adjusting, "Transmission Hydraulic Control Pilot Pressure - Test and Adjust".Problem: The pressures at all the clutches are low in torque converter drive only.
Probable Cause
The transmission charging pump section is bad. Perform the procedure in the Power Train Testing and Adjusting, "Transmission Hydraulic Control (Pressure Pack) - Test and Adjust".
There is a restriction in the transmission charging hydraulic filter and/or other components.
The pressures in the transmission selector and pressure control valve are incorrectly set. Perform the procedure in the Power Train Testing and Adjusting, "Transmission Hydraulic Control (Pressure Pack) - Test and Adjust".Problem: The pressures at all the clutches are low in direct drive only.
Probable Cause
The pressures in the selector and pressure control valve are incorrect. Perform the procedure in the Power Train Testing and Adjusting, "Transmission Hydraulic Control (Pressure Pack) - Test and Adjust".Problem: The pressure at any clutch is 0 kPa (0 psi).
Probable Cause
Selector piston plug (5) is not installed.
The supply port of the rotary selector spool is plugged.Problem: The pressure in a clutch does not increase above the primary pressure.
Probable Cause
Load piston plug (9) is not installed.
Load piston orifice (7) is plugged.
There are broken springs in modulation reduction valve (6) .Problem: The pressure in only one clutch is not correct, but the primary pressure in the same clutch is correct.
Probable Cause
There are broken springs in modulation reduction valve (6) .
Incorrect components or damaged components in the pressure control valveProblem: The pressure in one clutch at the high idle rpm is correct, but the pressure in the same clutch at the low idle rpm is not correct.
Probable CauseThere are bad seals in a clutch of the transmission.Problem: The pressure in one clutch does not decrease rapidly or the low pressure remains in one clutch.
Probable Cause
Decay orifice (8) is plugged.
The drain passage in the return end of the rotary selector spool is plugged.Problem: An additional clutch receives pressure oil in certain speeds.
Probable Cause
Decay orifice (8) is plugged.
The drain passage in the return end of the rotary selector spool is plugged.