821889A49 Mercury REV LIMITER

Sudden movement of the machine or release of oil under pressure can cause serious injury to persons on or near the machine.To prevent possible injury, perform the procedure that follows before testing and adjusting the hydraulic system.
Personal injury or death can result from escaping fluid under pressure.Escaping fluid under pressure, even a very small pin-hole size leak, can penetrate body tissue and cause serious injury and possible death. If fluid is injected into your skin, it must be treated by a doctor familiar with this type of injury.Always use a board or cardboard when checking for a leak.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat products.Dispose of all fluids according to local regulations and mandates.
Introduction
The following procedure will release the pressure in the hydraulic system.Required Tools
Table 1
Required Tools
Tool Item Qty Part No Description
B B1 1 8T-0860 Pressure Gauge
0 to 40,000 kPa (0 to 5,800 psi)
B2 1 6V-3989 Fitting
B3 2 6V-4143 Quick Connect Coupler
B4 1 177-7861 Hose As
4.3 m (14 ft)
Illustration 1 g02726620
Tooling (B)
Test Preparation
Move the machine to a hard, level surface.
Place the transmission direction in the NEUTRAL position and speed control in any speed position. Engage the steering and transmission lock lever.
Engage the parking brake. Place wheel blocks in front of the wheels and behind the wheels.
When the work tool is raised for testing or for adjusting, make sure that the work tool is supported correctly. Also, make sure that the work tool is fully in the DUMP position. The lift circuit has high oil pressure when the lift arms raise the front of the machine. Note: Do not stop the machine with the front of the machine off the ground unless required for a test. Lower the machine to the ground and stop the engine.
With machines equipped with the ride control system, increase engine speed above 1500 rpm, press, and hold the ride control switch in the SERVICE position. Move the joystick control lever to the FLOAT position, in order to relieve all of the hydraulic pressure in the ride control accumulator.
Decrease the engine speed to low idle.
Stop the engine.
Install the steering frame lock. Refer to Operation and Maintenance Manual, "Steering Frame Lock".
Move the key start switch to the ON position.
Move the joystick control lever through the full range of travel in order to relieve pressure that may be present in the implement hydraulic system.
Move the steering control several times in both directions to release the pressure in the steering system.
Release the braking system oil pressure. Refer to Systems Operation, Testing and Adjusting, Braking System, "System Pressure - Release".
Depress the breaker relief valve on the hydraulic tank to release the pressure in the hydraulic tank. Test Procedure
Illustration 2 g03061717
(1) Pressure tap (for the head end of the tilt cylinder)
Illustration 3 g03061716
(2) Pressure tap (for the rod end of the tilt cylinder)
Connect Tooling (B) to pressure tap (1). If pressure registers on the gauge, move the joystick control lever through the full range of travel to release the pressure from the system.
Connect Tooling (B) to pressure tap (2). If pressure registers on the gauge, move the joystick control lever through the full range of travel to release the pressure from the system.
The pressure in the hydraulic system has now been released. The lines, fittings, and components can be removed.
Remove Tooling (B).