Briggs & Stratton 083100 User manual

Foreword
This manual was written to assist engine technicians and service personnel with the repair and maintenance
procedures for Briggs & Stratton® engines. It assumes that persons using this manual have been properly
trained in and are familiar with the servicing procedures for these products, including the proper use of
required tools and safety equipment and the application of appropriate safety practices. Persons untrained
or unfamiliar with these procedures or products should not attempt to perform such work.
Proper maintenance and repair is important to safe, reliable operation of all engines and engine-driven
systems. The troubleshooting, testing, maintenance, and repair procedures described in this manual are
appropriate for the Briggs & Stratton engines described herein. Alternative methods or procedures may pose
risk to personal safety and the safety and/or reliability of the engine and are not endorsed or recommended
by Briggs & Stratton.
All information, illustrations, and specifications contained in this manual were based on the data available
at the time of publication. Briggs & Stratton Corporation reserves the right to change, alter, or otherwise
improve the product or the product manuals at any time without prior notice.
Briggs & Stratton offers two complementary publications to enhance understanding of engine technology,
maintenance, and repair. (Neither publication, however, is a substitution for a recognized training program
for engine technicians.)
•For consumers, Small Engine and Equipment Maintenance Guide (p/n CE8155) provides a comprehensive
overview of how small air-cooled engines work, basic troubleshooting, and step-by-step maintenance
procedures.
• For engine technicians and consumers alike, an in-depth study of engine theory and operation can be
found in the textbook Small Engines (p/n CE8020).
Both publications can be purchased at BRIGGSandSTRATTON.COM or through a local Briggs & Stratton
Authorized Service Dealer.
Copyright © 2015 Briggs & Stratton Corporation.
All rights reserved.
No part of this manual may be reproduced or transmitted in any form or by any means, electronic or
mechanical, including photocopying or recording by any information storage and retrieval system, without
prior written permission from Briggs & Stratton Corporation.

This engine repair manual includes the following engine model:
• MODEL 083100

1
SECTION 1 – GENERAL INFORMATION
2
SECTION 2 – SAFETY, MAINTENANCE AND ADJUSTMENTS
3
SECTION 3 – TROUBLESHOOTING
4
SECTION 4 – FUEL SYSTEM AND CARBURETION
5
SECTION 5 – CONTROLS AND GOVERNOR SYSTEM
6
SECTION 6 – LUBRICATION SYSTEM
7
SECTION 7 – CYLINDER HEAD AND VALVES
8
SECTION 8 – PISTON, RINGS AND CONNECTING ROD
9
SECTION 9 – CRANKSHAFT, CAMSHAFT AND FLYWHEEL
10
SECTION 10 – CYLINDER AND CRANKCASE COVER
11
SECTION 11 – GEAR REDUCTION UNIT
12
SECTION 12 – STARTER
13
SECTION 13 – EXHAUST SYSTEM
14
SECTION 14 – ENGINE SPECIFICATIONS

SECTION 1 – GENERAL INFORMATION
GENERAL INFORMATION - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4
Engine Identification - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4
Acronyms, Abbreviations and Meanings - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4
Order of Engine Assembly and Disassembly - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4
3
1

GENERAL INFORMATION
Engine Identification
Engine identification is located as shown (A).
1
Acronyms, Abbreviations and Meanings
MeaningAcronyms and
Abbreviations
Bottom Dead CenterBDC
Before Top Dead CenterBTDC
MagnetoMAG
Part Numberp/n
Power Take-OffPTO
Revolutions Per MinuteRPM
Top Dead CenterTDC
Top No-LoadTNL
Order of Engine Assembly and Disassembly
Section ProcedureSection
Number
Order of Disassembly
Change Oil2Drain oil
Service Spark Plug2Spark Plug
Change Air Filter2Air cleaner assembly
Section ProcedureSection
Number
Order of Disassembly
Remove Control Bracket5Control panel trim
Remove Control Bracket5Governor control bracket
Remove Control Bracket5Air cleaner base
Remove Carburetor4Carburetor
Disassemble Carburetor4Disassemble carburetor
Remove Fuel Tank4Fuel tank
Remove Rewind Starter12Rewind starter
Adjust Armature Air Gap2Blower housing
Remove Muffler13Exhaust manifold
Remove Flywheel9Armature
Remove Flywheel9Flywheel
Remove Breather6Rocker cover / breather
Remove Cylinder Head7Cylinder shield
Disassemble Cylinder Head7Rocker arms
Remove Cylinder Head7Push rods
Remove Cylinder Head7Cylinder head
Disassemble Cylinder Head7Valves, springs and seals
Remove Crankshaft and
Camshaft
9Crankcase cover
Remove PTO Bearing10PTO oil seal
Remove PTO Bearing10PTO bearing
Remove Crankshaft and
Camshaft
9Camshaft and tappets
Remove Piston and
Connecting Rod
8Connecting rod and piston
Remove Crankshaft and
Camshaft
9Crankshaft
Remove MAG Bearing10MAG oil seal
Remove MAG Bearing10MAG bearing
Section ProcedureSection
Number
Order of Assembly
Install MAG Bearing10MAG bearing
Install MAG Bearing10MAG oil seal
Install Crankshaft and
Camshaft
9Crankshaft
Install Piston and Connecting
Rod
8Connecting rod and piston
Install Crankshaft and
Camshaft
9Camshaft and tappets
Install PTO Bearing10PTO bearing
Install PTO Bearing10PTO oil seal
Install Crankcase Cover9Crankcase cover
Assemble Cylinder Head7Valves, springs and seals
Install Cylinder Head7Cylinder head
Install Cylinder Head7Push rods
Install Cylinder Head7Rocker arms
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Section ProcedureSection
Number
Order of Assembly
Adjust Valve Clearance2Adjust valve clearance
Install Breather6Rocker cover / breather
Install Cylinder Head7Cylinder shield
Install Flywheel9Flywheel
Install Flywheel9Armature
Adjust Armature Air Gap2Adjust armature air gap
Adjust Armature Air Gap2Blower housing
Install Rewind Starter12Rewind starter
Assemble Carburetor4Assemble carburetor
Install Carburetor4Carburetor
Install Control Bracket5Governor control bracket
Perform Static Governor
Adjustment
2Static governor adjustment
Install Control Bracket5Air cleaner base
Install Fuel Tank4Fuel tank
Install Control Bracket5Control panel trim
Change Air Filter2Air cleaner assembly
Install Muffler13Exhaust manifold
Service Spark Plug2Spark Plug
Change Oil2Fill engine with oil
5
1

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SECTION 2 – SAFETY, MAINTENANCE AND ADJUSTMENTS
SAFETY INFORMATION - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 8
Safety Alert Symbol and Signal Words - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 8
Hazard Symbols and Meanings - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 8
General Safety Messages - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 8
ENGINE MAINTENANCE - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 11
Maintenance Schedule - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 12
Fuel Recommendations - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 12
High Altitude - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 12
Oil Recommendations - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 12
Service Fuel Filter - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 12
In-Tank Fuel Filter - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 12
In-Line Fuel Filter - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 13
Change Oil - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 14
Change Air Filter - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 15
Service Spark Plug - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 16
Clean Air Cooling System - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 16
Clean Combustion Chamber - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 17
Storage - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 17
ENGINE ADJUSTMENTS - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 17
Adjust Armature Air Gap - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 18
Carburetor - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 19
Adjust Idle Speed - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 19
Remote Choke and Throttle Controls - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 19
Adjust Remote Choke Control - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 19
Adjust Remote Throttle Control - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 20
Governor - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 20
Perform Static Governor Adjustment - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 20
Adjust Idle Speed - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 21
Adjust Top No-Load Speed - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 21
Combustion Chamber - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 21
Adjust Valve Clearance - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 21
7
2

SAFETY INFORMATION
This repair manual contains safety information that is
designed to:
• Make you aware of hazards associated with engines.
• Inform you of the risk of injury associated with those
hazards.
• Instruct you how to avoid or reduce the risk of injury.
Safety Alert Symbol and Signal Words
The safety alert symbol indicates a potential personal
injury hazard. A signal word (DANGER,WARNING, or
CAUTION) is used with the alert symbol to designate a
degree or level of hazard seriousness. A safety symbol may
be used to represent the type of hazard. The signal word
NOTICE is used to address practices not related to personal
injury.
DANGER indicates a hazard which, if not avoided, will
result in death or serious injury.
WARNING indicates a hazard which, if not avoided,
could result in death or serious injury.
CAUTION indicates a hazard which, if not avoided,
could result in minor or moderate injury.
NOTICE addresses practices not related to personal injury.
Hazard Symbols and Meanings
MeaningSymbolMeaningSymbol
Read and understand the
Operator's Manual before
operating or servicing the
unit.
Safety information
about hazards that can
result in personal
injury.
Explosion hazardFire hazard
Explosion hazardShock hazard
Toxic fume hazardHot surface hazard
Chemical hazardAmputation hazard -
moving parts
MeaningSymbolMeaningSymbol
Thrown object hazard -
wear eye protection
Kickback hazard
Amputation hazard -
entanglement
General Safety Messages
Prior to work, read and understand the section(s) of this
manual that pertain to the job. Follow all safety warnings.
• Always use fresh gasoline. Stale fuel can cause gum
deposits in the carburetor and cause leakage, flow
restrictions, or other problems.
• Check fuel lines and fittings frequently for cracks or
leaks and replace if necessary.
WARNING
Before attempting to service this equipment, read and
understand this manual and the operating instructions of
the engine and the equipment.
WARNING
Failure to follow instructions could result in serious injury
(including paralysis) and even death.
WARNING
Battery post, terminals, and related accessories contain
lead and lead compounds - chemicals known to the State
of California to cause cancer and reproductive harm. Wash
hands after handling.
WARNING
Certain components in this product and its related
accessories contain chemicals known to the State of
California to cause cancer, birth defects, or other
reproductive harm. Wash hands after handling.
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