Service Manual Instruction Manual
Table Of Contents
- Section A. Introduction - Maintenance Safety Precautions
- Section 1. Specifications
- Section 2. General
- Section 3. Chassis & Turntable
- 3.1 Tires And Wheels
- 3.2 Torque Hub
- Oil Information
- Roll and Leak Testing
- Tightening and Torquing Bolts
- Main Disassembly
- Output Carrier Disassembly
- Input Carrier Disassembly
- Hub-Spindle Disassembly
- Spindle-Brake Disassembly
- Cover Disassembly
- Cover Assembly
- Input Carrier Sub-Assembly
- Output Planet Gear Sub-Assembly
- Spindle - Brake Sub-Assembly
- Hub-Spindle Sub-Assembly
- Cover Sub-Assembly
- Main Assembly
- Integral Brake Check
- 3.3 Free Wheeling Option
- 3.4 Drive Motor
- 3.5 Oscillating Axle Bleeding Procedure and Lockout Test
- 3.6 Steer Adjustments
- 3.7 Swing Drive
- 3.8 Swing Bearing
- 3.9 Swing Brake - Mico
- 3.10 Rotary Coupling
- 3.11 Generator
- 3.12 Deutz D2.9 L4 Engine
- 3.13 Deutz D2011 Engine
- 3.14 Spark Arrester Cleaning Instructions
- 3.15 Glow Plugs
- 3.16 Deutz EMR 2
- 3.17 Bio Fuel in Deutz Engines
- 3.18 GM Engine General Maintenance
- 3.19 GM Engine Dual Fuel System
- Fuel Filter
- Direct Electronic Pressure Regulator (DEPR)
- Air Fuel Mixer
- Electronic Throttle Control (ETC)
- Electric Lock Off
- Engine Control Module (ECM)
- Heated Exhaust Gas Oxygen Sensor
- Gasoline Multi Point Fuel Injection System (MPFI)
- Gasoline Fuel Pump
- Gasoline Pressure And Temperature Sensor Manifold
- Fuel Filter
- Fuel Injector Rail
- Fuel Injector
- 3.20 GM Engine Fuel System Repair
- Propane Fuel System Pressure Relief
- Propane Fuel System Leak Test
- Propane Fuel Filter Replacement
- Direct Electronic Pressure Regulator (DEPR) Maintenance And Inspection
- Check/Drain Oil Build-Up In 2-Stage Vaporizer
- Air Fuel Mixer/Throttle Control Device Maintenance And Inspection
- Exhaust System And Catalytic Converter Inspection And Maintenance
- Temperature Manifold Absolute Pressure (TMAP) Sensor
- Throttle Body (ETC) Replacement
- Mixer Replacement
- Electronic Pressure Regulator (EPR) Replacement
- Regulator Replacement
- Coolant Hose Replacement
- Vapor Hose Replacement
- Engine Control Module Replacement
- Heated Exhaust Gas Oxygen Sensor Replacement
- 3.21 GM Engine LPG Fuel System Diagnosis
- Section 4. Boom & Platform
- Section 5. Hydraulics
- 5.1 O-Ring Lubrication
- 5.2 Cylinders - Theory of Operation
- 5.3 Cylinder Checking Procedure
- 5.4 Cylinder Removal and Installation
- Cylinder Locations
- Main Boom Telescope Cylinder Removal
- Main Boom Telescope Cylinder Installation
- Main Boom Lift Cylinder Removal
- Main Boom Lift Cylinder Installation
- Upright Level Cylinder Removal
- Upright Level Cylinder Installation
- Tower Boom Lift Cylinder Removal
- Tower Lift Cylinder Installation
- Tower Telescope Cylinder Removal
- Tower Telescope Cylinder Installation
- 5.5 Hydraulic Cylinder repair
- Tower Boom Lift Cylinder
- Cleaning and Inspection
- Assembly
- Upright Level Cylinder
- Cleaning and Inspection
- Assembly
- Master Cylinder
- Cleaning and Inspection
- Assembly
- Main Boom Lift Cylinder
- Cleaning and Inspection
- Assembly
- Main Boom Telescope Cylinder
- Cleaning and Inspection
- Assembly
- Tower Boom Telescope Cylinder
- Cleaning and Inspection
- Assembly
- Platform Level (Slave) Cylinder
- Cleaning and Inspection
- Assembly
- Jib Lift Cylinder (AJ Only)
- Cleaning and Inspection
- Assembly
- Steer Cylinder
- Cleaning and Inspection
- Assembly
- Axle Lockout Cylinder
- 5.6 Hydraulic Pump (Gear)
- 5.7 Variable Pump
- 5.8 Hydraulic Component Start-Up
- 5.9 Pressure Setting Procedures
- Section 6. JLG Control System
- Section 7. Basic Electrical Information & Schematics
SECTION 3 - CHASSIS & TURNTABLE
3121616 – JLG Lift – 3-91
3.21 GM ENGINE LPG FUEL SYSTEM DIAGNOSIS
Fuel System Description
Figure 3-103. DEPR
The Engine Control Module (ECM) receives information from
various engine sensors to control the Direct Electronic Pres-
sure Regulator (DEPR) and lock-off Valve.
The lock-off Valve solenoid prevents fuel flow unless the
engine is cranking or running.
At Key ON, the DEPR valve receives a two (2) second prime
pulse from the ECM, allowing time for the fuel to flow through
the fuel filter and fuel lines to the DEPR.
Fuel travels from the lock-off to the light duty 2- stage regula-
tor into the DEPR.
Engine cranking generates vacuum which provided lift for the
mixer air valve and is commonly referred to as air valve vac-
uum. Once in the mixer, fuel is combined with air and drawn
into the engine for combustion.
Diagnostic Aids
This procedure is intended to diagnose a vehicle operating on
LPG. If vehicle will not continue to run on LPG, refer to Hard
Start for preliminary checks.
NOTE: Before proceeding with this procedure, verify vehicle has a
sufficient quantity of fuel and that liquid fuel is being deliv-
ered to the LPR. Ensure the LPG tank manual shut off valve
is fully opened and excess flow valve has not been acti-
vated.
Tools Required:
• 7/16 Open end wrench (for test port plugs)
• DVOM (GM J 39200, Fluke 88 or equivalent).
• 12 volt test light
Diagnostic Scan Tool
• Diagnostic Display tool.
Pressure Gauges
•IMPCO ITK-2 Test kit
• Water Column Gauge / Manometer (GM 7333-6 or equiva-
lent).
• 0-10 PSI Gauge
Test Description
Numbers below refer to step numbers on the diagnostic table.
5. This step determines if the LPR requires replacement
6. This step determines if the problems are in the mechanical
side of the Pressure Regulator or the Electronic Voice Coil
10. This step determines if the Mixer requires replacement
14. This step determines if the Lock Off requires replacement
17. This step determines if the Fuel Filter requires replacement.