SOLENOID 4N7154 - Caterpillar

Adjusting The Cut-Out Pressure
The following procedure can be used on all D20D, D250D, D300D, D250E and D300E Articulated Trucks.
Stop the engine and operate the service brake in order to remove all brake pressure.
Install a pressure gauge in the tractor brake system. See the References.
Start and operate the engine at low idle in order to charge the brake system. Note the gauge pressure at the cut out point when the pressure stops rising. The gauge pressure should be 17000 kPa (2465 psi) to 18000 kPa (2610 psi) at the cut out point.
If the pressure is lower than 17000 kPa (2465 psi), stop the engine and operate the service brake in order to remove the system pressure. Loosen jam nut (3) and turn adjuster (4) clockwise in order to increase the cut out pressure.
Repeat Steps 3 and 4 until the correct cut out pressure is obtained. See Illustrations 1 and 2. Check that Dimension (A) is 8.75 1.25 mm (0.35 0.05 inch).
Illustration 1 g01197583
Brake accumulator charging valve location
Illustration 2 g01197584
Detail X (1) Jam nut (2) Adjuster (3) Jam nut (4) Adjuster (5) PlugAdjusting The Cut-In Pressure
Start the engine and operate the engine at low idle until the brake system is fully charged.
Lightly apply the brake in order to decrease the system pressure. When the cut-in pressure is reached, and the hydraulic pump starts to charge the system, the gauge needle will move suddenly. The cut-in pressure should be between 15000 kPa (2175 psi) and 16000 kPa (2320 psi).
If the cut-in pressure is not between 15000 kPa (2175 psi) and 16000 kPa (2320 psi), stop the engine and relieve the brake pressure.
Remove plug (5) and loosen jam nut (1). Turn adjuster (2) clockwise in order to increase the pressure setting. Turning the adjuster counterclockwise will decrease the pressure setting.
Repeat Steps 1 through 4 until the correct cut-in pressure is obtained. Tighten all jam nuts and install the plug.