9101140620 Tohatsu BOLT

Introduction
Table 1
Revision History
Revison Summary of Changes
05 Added torque value to Step 6 under Illustration 8. Do not perform any procedure that is outlined in this Special Instruction and do not order any parts until the entire instruction has been read and understood.This Special Instruction describes the installation of the Hydrax system on G3612 and on G3616 Engines. The Hydrax system replaces the electronic actuators that control the fuel, the wastegate, and the choke. The Hydrax system improves the reliability of the engine and the system reduces maintenance costs.Whenever questions arise about this product or about this Special Instruction, consult your local Caterpillar dealer for the latest available information.References
The following reference materials may be necessary for this procedure:Specifications, SENR5527Troubleshooting, SENR6510Disassembly And Assembly Manual, SENR5535Systems Operation/Testing and Adjusting, RENR5528System Description
Illustration 1 g01028469
Left side view of the engine
(1) Position sensor
(2) Air choke actuator
(3) Hydraulic pump
(4) Hydraulic tank
(5) Hydraulic oil filter
(6) Accumulator
(7) Check valve
Illustration 2 g01028474
Right side view of the engine
(8) Wastegate actuator
(9) Fuel actuator
(10) Pressure relief valve
(11) Pressure switch
(12) Box for the hydrax driver modulesThe Hydrax system controls fuel actuator (9), wastegate actuator (8), and air choke actuator (2) by using individual electronically controlled hydraulic actuators.The system uses engine oil or hydraulic oil for the hydraulic fluid. Hydraulic pump (3) is driven by the engine. The pump provides the required fluid pressure. The pump is gear-driven from the engine front gear train. The pump is mounted behind the engine oil pump. The pump will provide hydraulic fluid at approximately 8 gpm at 1000 rpm engine speed.Hydraulic tank (4) stores the hydraulic fluid. Check valve (7) keeps the oil from draining from the system. This provides better response characteristics.Accumulator (6) is a nitrogen charged bottle which maintains the system pressure. The accumulator maintains the system pressure for a short period of time after an engine shutdown condition is requested. This allows the occurrence of a proper shutdown sequence.Pressure switch (11) protects the engine in case of a reduction in the system pressure. The switch activates a warning if the system pressure drops below 1207 kPa (175 psi). An engine shutdown will occur if the system pressure drops below 690 103 kPa (100 15 psi).A hydraulic oil filter is inside housing (5).Pressure relief valve (10) is in parallel with the three actuators. The pressure relief valve is manually adjusted at rated engine speed in order to obtain a system pressure of 1550 kPa (225 psi).The actuators are electronically controlled. The engine's control system sends commands to three hydrax driver modules inside box (12). The modules convert the signals for use by the actuators.Position sensors (1) are connected to the linkage for each of the actuators. The feedback signals are sent to the hydrax driver modules. The signals from the driver modules are monitored by the Electronic Control Module.Note: The hydrax driver modules, the position sensors, and the accumulator are not required if the engine will be equipped with the ADEM III control system.The hydraulic actuators, the position sensors, and the driver modules are interchangeable. This simplifies troubleshooting the system.Parts List
The parts that are required for installation of the hydrax system are listed in Table 2.
Table 2
Parts List For the Hydraulic Actuator System
Part Number Quantity Description
G3612 Engine G3616 Engine
8T-9580 2 Hydraulic Oil
117-3195 117-3196 1 Hydraulic Tank and Mounting Group
142-4238 1 Exhaust Bypass Group
153-2789 1 Air Lines (Choke)
153-2788 1 Fuel Control
4C-4030 1 Thread Lock Compound
148-7632 148-7633 1 Engine Oil Lines
Pump and Hardware for the Pump
290-9753 1 Gear Pump Gp
1W-3389 1 Gear
1W-3390 1 Gear
1B-7182 1 Bolt
0L-1143 6 Bolt
0S-1585 2