Textron JACOBSEN GP400 User manual

GP400
Riding Greens Mower
Technical/Repair Manual
USAG004, USAD004

WARNING: If incorrectly used, this machine can cause severe injury. Those
who use and maintain this machine should be trained in its proper use,
warned of its dangers, and should read the entire manual before attempting to
set up, operate, adjust, or service the machine.
!
©2011 Jacobsen, A Textron Company. All rights reserved.
When Performance Matters.
™
Jake manual cover separate front1 1 12/18/06 4:19:12 PM
GP400
Riding Greens Mower
Technical/Repair Manual
USAG004, USAD004

4252490-Rev A 5
Litho In U.S.A. 01-2013
Foreword
General
This manual provides detailed information and
procedures to safely repair and maintain the following:
Jacobsen GP400 riding greens mower and
associated accessory attachments
This manual is intended to introduce and guide the user
through the latest factory-approved troubleshooting and
repair techniques and practices.
Before you attempt to troubleshoot or make repairs, you
must be familiar with the operation of this machine. Refer
to the operator’s manual and parts manual for specific
information on these topics.
THE INFORMATION CONTAINED IN THIS MANUAL IS
BASED ON MACHINES MANUFACTURED UP TO THE
TIME OF PUBLICATION. JACOBSEN RESERVES THE
RIGHT TO CHANGE ANY OF THIS INFORMATION
WITHOUT NOTICE.
California
Proposition 65 Warning
!
WARNING
Trademark Acknowledgement
Jacobsen acknowledges the following trademarks for
company names or products mentioned within this
publication:
Lubriplate®is a trademark of Fiske Brothers Refining Co.
Loctite®and Permatex®are trademarks of Henkel
Corporation.
Certain vehicle components contain or emit
chemicals known to the State of California to
cause cancer and birth defects or other
reproductive harm.

64252490-Rev A
FOREWORD
How to Use This Manual
This manual is designed to provide multiple ways to
locate and access repair information.
Read each section in its entirety before beginning a
procedure. Proper understanding of machine operation
and components is the key to successful diagnostics and
repair.
Make use of special information features within this
manual in order to be better prepared to perform repairs.
Always follow manual procedures and safety guidelines.
Never take shortcuts.
Table of Contents
Major machine components or topics of interest are
separated into specific chapters. Each manual lists these
chapters in a main Table of Contents.
Chapter Table of Contents
Each chapter begins with a detailed table of contents
related to the specific machine component or system.
Use the chapter table of contents to find specific
component or procedural information.
Index
An alphabetical Index is located at the back of the
manual.
Use the Index to find specific components and related
procedures.
Required Tools and Materials
Some procedures will require the use of specific tools
and/or materials. These tools and/or materials will be
listed for reference, prior to beginning a procedure.
Specifications
Near the beginning of each chapter is a specifications
listing. This listing contains any specifications contained
within the chapter.
Quick Reference Specifications
A list of all machine specifications can be found in
Chapter 2 Specifications and General Information. This is
a list of all specifications from each chapter, combined
and listed in one place for easy reference.
Warnings and Cautions
Warning and Caution indicators are located throughout
the manual at specific points of interest. These notices
are given to prevent personal injury, death, and/or
equipment damage. Always heed these notices, and
practice common sense when performing any
maintenance or repair procedure.
Notes
Special notes are given in order to draw attention to
detailed instructions. These notes are intended to give
further important information regarding the machine
and/or a step in a procedure.
Troubleshooting
Troubleshooting charts are provided in each chapter to
aid in the diagnostic process. Use these suggestions to
aid in identifying a potential mechanical or machine
adjustment problem.
Copyright 2011, Jacobsen, A Textron Company
“All rights reserved, including the right to reproduce this material or portions thereof in any form.”

9
2
3
4
5
6
7
8
Table of Contents
4252490-Rev A 7
1
Safety
Specifications and
General Information
Engine
Electrical
Hydrostatic Power Train
Hydraulics
Steering
Cutting Units
Accessories and Miscellaneous
Repair

4252490-Rev A 1-1
Chapter 1
1
Safety
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Prepare for the Job . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Safety Notices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Safety Label Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Inspect Safety Labels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Keep Work Area Clean . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Keep Work Area Well Ventilated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Use Proper Eye and Face Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Park Mower Safely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Use Lifting Equipment Safely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Support Machine Securely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Use Compressed Air and Air Tools Safely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Service Tires Safely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Handle Fuel Safely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Store Volatile and Hazardous Materials Safely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Handle Chemical Products Safely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
Service Hydraulic System Safely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
Service Cooling System Safely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
Service Electrical Components Safely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
Dispose of Waste Materials Safely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10

1-2 4252490-Rev A
SAFETY
1
Introduction
Safety is the most important element of any repair
procedure. Knowledge of the procedure to be performed
and safe work habits are essential to preventing death,
personal injury, or property damage. Use the following
statements as a common-sense guide to proper work
and tool-use habits.
Prepare for the Job
Preparation is essential to complete a procedure in a
safe and efficient manner.
• Wear proper clothing. Loose or baggy clothing could
become tangled in moving parts.
• Use eye/face protection. Always use proper eye/face
protection to protect your eyes from flying debris or
chemical splatters.
• Wear protective footwear. Wear safety shoes
(steel-toe) to protect your feet from falling objects.
• Use gloves when handling parts. Parts may have
sharp edges or may be hot.
• Remove jewelry prior to servicing electrical systems.
• Prepare proper tools and equipment. Always use the
correct tool for the job. Improper or homemade tools
can cause injury or machine damage.
• Prepare needed parts and materials. Gather the
needed parts and materials before beginning the
procedure.
• Allow machine to cool.Many components can get hot
during operation. Be sure to allow enough time for
components to cool before beginning service.
• Prepare proper work-space lighting. A well-lit work
area can make the job easier.
• Follow procedures and safety warnings. Service
procedures are written to be as safe and efficient as
possible. Never take shortcuts.
• Be prepared for emergencies. Accidents can
happen, even under the best conditions. Fire
extinguishers and first aid kits should be well
maintained and easily accessible.
Safety Notices
Throughout this manual, the following key safety words
will be used to alert the reader of potential hazards.
Become familiar with these words and their meaning.
Take all precautions to avoid the hazards described.
!
DANGER
!
WARNING
!
CAUTION
NOTICE
Safety Label Locations
Become familiar with machine safety labels and
locations. The following illustrations show safety label
locations on the machine.
See Figure 1-1.
This safety alert symbol is used to
alert you to potential hazards.
Indicates an imminently hazardous situation
which, if not avoided, WILL result in death or
serious injury.
Indicates a potentially hazardoussituation which,
if not avoided, COULD result in death or serious
injury.
Indicates a potentially hazardoussituation which,
if not avoided, MAY result in minor or moderate
injury and property damage. It may also be used
to alert against unsafe practices.
Indicates a potentially hazardoussituation which,
if not avoided, MAY result in property damage. It
may also be used to alert against unsafe
practices.
!

SAFETY
4252490-Rev A 1-3
1
Figure 1-1 TN3769
11
9
5
10
12
4
6
7
8
3

1-4 4252490-Rev A
SAFETY
1
7
16
11
8
5

SAFETY
4252490-Rev A 1-5
1
Pb
42
3
14
10
4127335 SRC
9

1-6 4252490-Rev A
SAFETY
1
Inspect Safety Labels
Safety decals are critical to the safe operation of the
mower. Inspect the mower for any damaged, missing, or
unreadable decals. Replace decals as needed before
placing the mower back in service.
Keep Work Area Clean
A clean, organized, well-lit work area is important to
promote safe working conditions.
• Keep floor clean of debris and clear of parts and
tools.
• Clean up any spilled fuel, oil, and/or chemicals
immediately.
• Store all air hoses and electrical cords properly when
not in use.
Keep Work Area Well Ventilated
!
WARNING
Certain test and adjustment procedures require the
engine to be running. Be sure work area is well
ventilated; never run the engine in an enclosed area.
Use Proper Eye and Face
Protection
!
WARNING
Always wear eye protection while in a shop environment.
• Safety Glasses: Safety glasses offer a minimum level
of protection from flying debris.
• Face Shields: Face shields are often used along with
safety glasses to offer a higher level of protection
when sparks and flying debris are present.
• Vented Goggles: Goggles offer side protection not
offered by safety glasses alone.
• Unvented Goggles: Unvented goggles offer
protection from chemical splashes and vapors.
Park Mower Safely
See Figure 1-2.
!
WARNING
1. Park the mower on a solid, level surface.
Figure 1-2
2. Disengage the cutting units by moving the mow
switch (6) to the off position.
3. Lower the cutting units by moving the raise/lower
switch (5) forward.
4. Move throttle lever (3) to the slow position.
5. Move traction lever (1) to the mow position.
6. Engage park brake lever (4) and rotate key switch (2)
fully counterclockwise to off position.
7. Remove key from key switch.
Never operate the engine without proper
ventilation; exhaust fumes can be fatal if inhaled.
Always use approved personal protection
equipment. Avoid workplace hazards by wearing
properly maintained, approved eye and face
protection. Failure to use appropriate protection
equipment may result in death or serious injury.
Before cleaning, adjusting, or repairing this
equipment, disengage all drives, engage park
brake, and stop engine to prevent injuries.
When performing maintenance other than
adjustments that require the engine to be
running, disconnect the battery negative cables
to prevent accidental starting and bodily injury.
TN3797
6
2
4
5
3
1

SAFETY
4252490-Rev A 1-7
1
Use Lifting Equipment Safely
!
WARNING
• Always use a lifting device with a lifting capacity
greater than the weight of the item being lifted.
• Secure the load to the lifting device using cables,
chains, or slings rated to handle the load being lifted.
Fasteners being used to connect lifting devices must
be strong enough to handle the load. Also be sure
the mounting point of load is strong enough to handle
the load.
• When using a lifting device, always connect the load
so it is balanced.
• Always use a lifting device on a hard, level surface.
• Lower the lifting device to the lowest point before
moving. Move the load slowly.
• Always support the load as soon as possible; never
leave a load suspended in mid-air.
Support Machine Securely
!
WARNING
Use Compressed Air and Air
Tools Safely
!
WARNING
• Compressed air is a useful tool when used in a safe
manner.
• Always use eye and ear protection while using
compressed air and air tools.
• When using air tools, do not exceed the air pressure
rating for the tool.
• When using an impact wrench, always use approved
impact sockets. Never use standard sockets on an
impact wrench.
• Disconnect the air supply before changing air tool
attachments.
• Never point air nozzles or air tools at another person.
• Always maintain air tools properly.
Always check the lifting capacity and condition of
hoists, slings, cables, or chains before use.
Using underrated or worn lifting components can
result in death or serious injury.
• Support the machine using properly rated
jackstands. Never work under a machine
supported only by a jack.
• Do not use wood or concrete blocks to
support the machine. Failure to properly
support the machine may result in death or
serious injury.
Always wear approved eye and ear protection
while using compressed air. Misuse of
compressed air could result in death or serious
injury.
• When using air nozzles, air pressure should
not exceed 30 psi (206.8 kPa).
• Never direct air nozzles or tools at a person.
• Never point air nozzles directly at skin.

1-8 4252490-Rev A
SAFETY
1
Service Tires Safely
!
WARNING
• Always wear safety glasses or goggles.
• Use proper lifting methods when working with wheels
and tires.
• When working on an inflated tire, never position
yourself directly over the work area.
• When dismounting or mounting tires, use a wheel
holder or tire machine. Use proper tire mounting tools
and equipment. Never use screwdrivers or makeshift
tools to force a tire on or off a wheel.
• Be sure tire irons and mounting tools are free of
grease and oil. Grip them firmly.
• Inspect wheel parts for rust, damage, or distortion.
Never use wheels that are out-of-round, rusted, or
cracked.
• Never hammer on wheels with a steel hammer. Use
rubber-covered hammers.
• When inflating tires, always use an inflation cage.
Always stand away from the valve stem.
• Use accurate, tested inflation gauges to set air
pressures.
Handle Fuel Safely
Handle fuel with care—it is highly flammable.
!
WARNING
Store fuel according to local, state, or federal ordinances
and recommendations from your fuel supplier.
Never overfill or allow the tank to become empty.
Use clean, fresh fuel.
Do not fill above the fuel filler neck.
Store Volatile and Hazardous
Materials Safely
Store volatile materials (gasoline, diesel fuel, oil, etc.) in
approved containers that are clearly marked. Containers
should be stored in an approved safety cabinet away
from possible sources of ignition. Storage areas and
cabinets should be well ventilated to prevent the possible
build-up of fumes.
An inflated tire contains explosive force. Use care
when handling wheels and tires. • Never remove the fuel cap from the fuel tank,
or add fuel, when the engine is running or
while the engine is hot.
• Do not smoke when handling fuel. Never fill
or drain the fuel tank indoors.
• Do not spill fuel. Clean spilled fuel
immediately.
• Never handle or store fuel containers near an
open flame or any device that may create
sparks and ignite the fuel or fuel vapors.
• Be sure to reinstall and tighten fuel cap
securely.
• Use an approved container; the spout must fit
inside the fuel filler neck. Avoid using cans
and funnels to transfer fuel.

SAFETY
4252490-Rev A 1-9
1
Handle Chemical Products
Safely
!
WARNING
Routine service often requires the use of various
chemical products, including lubricants and cleaning
solutions. Many of these chemicals are flammable and
can pose health risks if not handled properly.
• Never mix chemicals. Mixing chemicals can produce
toxic or explosive results.
• Follow the manufacture’s recommendations for safe
usage and handling of the product.
• Various materials may pose a health hazard if used
incorrectly. A Material Safety Data Sheet (MSDS)
contains important information regarding proper
handling and health hazards, as well as emergency
response procedures. Contact the chemical
manufacturer to obtain an MSDS for the chemical
product.
Service Hydraulic System Safely
!
WARNING
Always dispose of used hydraulic oil properly. (See
“Dispose of Waste Materials Safely” on page 1-10.)
Service Cooling System Safely
!
WARNING
!
WARNING
Always dispose of used engine coolant properly. (See
“Dispose of Waste Materials Safely” on page 1-10.)
Exposure to chemical products could result in
serious injury. Handle chemical products with
care. Refer to the chemical manufacturer’s
Material Safety Data Sheet (MSDS) for
information regarding health hazards, safe
handling, and emergency response procedures.
The hydraulic system is under pressure, and the
oil may be hot!
• Always allow the machine to cool completely
before performing service.
• Always relieve pressure in the hydraulic
system before performing service.
• Always use appropriate safety equipment and
clothing to protect exposed skin and eyes
from high-pressure oil.
• Tighten all connections to proper
specifications before applying pressure.
• Never use bare hands to check for leaks! Oil
under pressure can penetrate the skin, and
can cause gangrene within a few hours if not
properly removed. Use a piece of cardboard
to check for leaks.
Failure to follow appropriate safety precautions
may result in death or serious injury.
Engine coolant is hot and under pressure! Allow
the cooling system to cool completely before
performing service.
Rotate the filler cap 1/2-turn counterclockwise
and allow pressure to vent before removing filler
cap.
Failure to follow appropriate safety precautions
may result in death or serious injury.
Contact with anti-freeze can damage your skin.
Use gloves when working with anti-freeze. If you
come in contact with anti-freeze, wash it off
immediately.

1-10 4252490-Rev A
SAFETY
1
Service Electrical Components
Safely
!
WARNING
• Disconnect the battery negative (–) cable before
removing or installing electrical components. Always
connect the battery negative (–) cable last.
• Certain test and adjustment procedures must be
performed with the battery connected. Use care to
prevent arcing when working on live circuits or
components. Arcing can cause component damage
and could ignite flammable materials.
Dispose of Waste Materials
Safely
Routine service can produce waste products such as
used oil, coolant, grease, and used batteries.
If not handled properly, these materials can pose a threat
to the environment.
Collect fluids in well-marked, approved storage
containers. Some waste fluids can react with certain
types of plastics. Make sure the fluid to be stored is
compatible with the storage container. Never use food or
beverage containers to store waste fluids.
IMPORTANT
• Dispose of waste fluids properly at approved local
recycling centers. If recycling facilities are not
available, contact your local community for the
correct disposal procedure for waste fluids.
• Dispose of old batteries properly. Battery electrolyte
contains sulfuric acid and other hazardous materials.
Never place an old battery in the trash. Batteries
must be disposed of in a manner consistent with EPA
and/or local regulations.
Always disconnect the negative terminal first and
positive terminal last. Connect positive terminal
first and negative terminal last. Use care when
testing live circuits to prevent arcing. Arcing
could result in death or serious injury.
Never dispose of waste fluids by pouring on the
ground, down sewer drains, or into any body of
water.

2
4252490-Rev A 2-1
Chapter 2
Specifications and General Information
Machine Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Machine Serial Number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Engine Serial Number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Optional Machine Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Component Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
Quick Reference Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
Standard Torque Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
Inch Fastener Torque Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
Metric Fastener Torque Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
Hydraulic Hose, Tube, and Fitting General Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
O-Ring Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
Hose Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12

2-2 4252490-Rev A
SPECIFICATIONS AND GENERAL INFORMATION
2
Machine Identification
Machine Serial Number
See Figures 2-1 and 2-2.
Figure 2-1
Figure 2-2
A machine identification plate (1)listing the serial number
(3) and the machine weight (2) is attached to the rear
frame of the mower near the steering yoke. Always
provide the serial number of the machine when ordering
replacement parts or requesting service information.
Engine Serial Number
See Figure 2-3.
Figure 2-3
The engine serial number plate (1) is attached to the top
of the rocker arm cover. The plate also includes the
engine model number and the engine code number. An
engine data tag (2) is attached to the side of the rocker
arm cover. The tag includes information on valve
adjustment specifications, injector timing, engine idle
speed, and engine displacement.
Optional Machine Accessories
This manual is structured to cover all basic machine
components and repair. The addition of accessories can
affect certain troubleshooting, adjustment, and repair
procedures.
TN3769
1
Kg Kw Kg Kg
West Road
Ransomes Europark
Ipswich IP3 9TT
England
A565 C13.2 ABCD
RIDE ON REEL MOWER USAD004
GP400 DIESEL GY000301
TN3806
2
3
TN3811
2
1