Note: If the adjustment of the hoist lower valve is set too high, then too much oil can be diverted to the hoist system while the hoist system is in the float mode. This could cause the brake oil to heat up at a faster rate. This will also lower retarding capability.
- Adjustment Procedure
Note: Before performing this adjustment procedure, place the hoist lever in the hold position. Place the truck in a stationary position.
- Place a 3447 kPa (500 psi) pressure gauge on the hoist outlet port.
- With the body in the down position, move the hoist lever to the hold position.
- Enter the configuration parameters screen. Select "Service" from the pull-down menu in the ET.
- Change the adjustment of the hoist lower valve to the desired setting from −5° to +5°.
- While the engine is operating, move the hoist lever to the float position.
- Run the engine to HI idle. Verify that the pressure at the hoist outlet port is less than 1724 kPa (250 psi).
Note: If the pressure is greater than 1724 kPa (250 psi) then the adjustment is set too high. This could cause too much oil to be diverted to the hoist valve. The brake oil could overheat, if the operator was driving with the hoist lever in the float position. Lower the setting and repeat the procedure until the pressure is lower than 1724 kPa (250 psi).
Note: Some software versions do not support the adjustment for the hoist lower valve command. If the above tests are completed and the pressures are out of specification, then update the software to the latest software version. See Testing and Adjusting, "Electronic Control Module (ECM) - Flash Program" for information on updating the software.