Briggs & Stratton CE8070 User manual

Familiarization & Troubleshooting Guide
PRESSURE WASHER
BRIGGS & STRATTON CORPORATION
Milwaukee, WI 53201
Part No. B3277GS Rev. 0 11/98
Printed in U.S.A.
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Pressure Washer
Familiarization & Troubleshooting
Guide
Electronic Version #B3277 Rev. 1 4/03
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This guide has been written and published by Briggs & Stratton Corporation to aid our dealers' mechanics and
company service personnel when servicing the products described herein.
It is assumed that these personnel are familiar with the servicing procedures for these products, or like or similar
products, manufactured by Briggs & Stratton Corporation. It is also assumed that they have been trained in the
recommended servicing procedures for these products, which includes the use of mechanics hand tools and any
special tools that might be required.
Proper service and repair is important to the safe, economical and reliable operation of all engine driven systems.
The troubleshooting, testing, service and repair procedures described in this guide are effective methods of
performing such operations.
We could not possibly know of and advise the service trade of all conceivable procedures or methods by which a
service might be performed, nor of any possible hazards and/or results of each procedure or method. We have
not undertaken any such wide evaluation. Therefore, anyone who uses a procedure or method not described by
the manufacturer must first satisfy himself that neither his safety, nor the safety of the product, will be
endangered by the service or operating procedure selected.
All information, illustrations, and specifications contained in this guide are based on the latest production
information available at the time of publication. However, Briggs & Stratton Corporation reserves the right to
change, alter, or otherwise improve the product at any time without prior notice.
Some components or assemblies of the product described in this guide may not be considered repairable.
Disassembly, repair and reassembly of such components may not be included in this guide.
Copyright © 2003 Briggs & Stratton Corporation
All rights reserved.
No part of this material may be reproduced or transmitted, in any form or by any means, electronic or
mechanical, including photocopying, recording or by any information storage and retrieval system, without prior
permission in writing from Briggs & Stratton Corporation.

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1 • Operation 5
2 • Pressure Washer Components 7
Power Source 7
Pressure washer pumps 7
Inlet and Outlet Check Valves 8
Unloader - Pressure Regulator 8
Thermal Bypass System 9
Chemical Injection 9
Easy Start Valve 10
High Pressure Hose 11
Spray Guns 11
Spray Wands and Nozzles 12
3 • General Information 13
Part 1 - General Maintenance 13
Chemical Injection System 13
Inlet Water Supply Connector 13
Inlet Supply Filter/Strainer 13
Hose, Spray Gun and Wand Systems 13
Spray Nozzle Servicing 14
Part 2 - Lubrication 15
Check Pump Oil Level 15
Change Pump Oil 15
Part 3 - Storage 16
Pump Storage 16
Protection Against Freezing 16
Purging Air From the System 16
4 • Small Frame Electric Pump 17
Part 1 - Specifications and Views 17
Performance Specifications 17
Cross-Sectional View 18
Exploded View 20
Part 2 - Disassembly 22
General Information & Special Tools 22
Pump Head 22
Piston Housing Removal 23
Piston Housing Disassembly 24
Chemical Injection System 24
Auto Start Switch Assembly 25
Axial Cam 26
Part 3 - Inspection 27
Seals, O-Rings, and Gaskets 27
Piston & Spring Assemblies 27
Pump Head and Piston Housing 27
Axial Cam Drive Components 28
Part 4 - Reassembly 29
Pump Head Assembly 29
Auto Start Switch Assembly 29
Chemical Inject Assembly 30
Piston Housing Assembly 31
Pilot Spacer Installation 31
Pump Head Bolts 32
Assemble Axial Cam 32
Oil Fill 32
Main Component Assembly 32
Final Assembly and Test 33
Part 5 - Troubleshooting 34
TABLE OF CONTENTS
Table of Contents
Portable Pressure Washer Familiarization and Troubleshooting Guide

Small Frame Gas Pump 35
Part 1 - Specifications and Views 35
Performance Specifications 35
Cross-Sectional view 36
Exploded View 38
Part 2 - Disassembly 40
General Information & Special Tools 40
Pump Head 40
Piston & Unloader Housing Removal 40
Piston & Unloader Housing Disassembly 41
Chemical Injection System 42
Unloader 42
Engine Adapter 43
Part 3 - Inspection 43
Seals, O-Rings, and Gaskets 43
Piston & Spring Assemblies 43
Engine Adapter, Pump Head and
Piston/Unloader Housing 44
Axial Cam Drive Components 44
Part 4 - Reassembly 45
Engine Adapter 45
Unloader Assembly 45
Chemical Injection Assembly 45
Piston & Unloader Housing Assembly 46
Pump Head Assembly 46
Main Component Assembly 47
Pilot Spacer Installation 48
Pump Head Bolts 49
Oil Fill 49
Part 5 - Troubleshooting 50
5 • Medium Frame Pump 51
Part 1 - Specifications and Views 51
Performance Specifications 51
Cross-Sectional View 52
Exploded View 55
Part 2 - Disassembly 56
General Information & Special Tools 56
Pump Head 56
Axial Cam Drive Components 57
Pistons and Piston Springs 57
Pump Head 58
Spacer Plate 58
Inlet Check Valves 59
Outlet Check Valves 59
Unloader Spindle Assembly 59
Chemical Injection System 60
Thermal Bypass Actuator Removal 60
Part 3 - Inspection 61
Seals, O-Rings, and Gaskets 61
Seals 61
Check Valves 61
Head Gasket 61
Engine Adapter O-Rings 62
Engine Adapter, Pump Crankcase and
Spacer Plate/Head 62
Axial Cam Drive Components 62
Piston & Spring Assemblies 62
High Pressure Outlet/Chemical
Injection Assembly 63
Part 4 - Reassembly 64
Engine Adapter 64
Piston Oil Seals and Pistons 65
Spacer Plate 67
High Pressure Seal Assembly 67
Check Valve Assembly 68
High Pressure Outlet and Chemical
Injection Assembly 69
Unloader Spindle Assembly 69
Pump Head Installation 70
Main Component Assembly 71
Oil Fill 72
Part 5 - Troubleshooting 73
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Table of Contents
Portable Pressure Washer Familiarization and Troubleshooting Guide
TABLE OF CONTENTS

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6 • Large Frame Pump 75
Part 1 - Specifications and Views 75
Performance Specifications 75
Cross-Sectional View 76
Exploded View 78
Part 2 - Disassembly 80
General Information & Special Tools 80
Pump Head 80
Axial Cam Drive Components
(Tapered Engine Shaft) 81
Axial Cam Drive Component
(Straight Engine Shaft) 82
Pistons and Piston Springs 82
Regulator/Unloader Valve 82
Cylinder Head 84
Thermal Bypass Actuator Removal 85
Spacer Plate 86
Part 3 - Inspection 87
Seals, O-Rings, and Gaskets 87
Oil Seals 87
Inlet Check Valve Seals 87
Outlet Check Valve Seals 87
Head Gasket 88
Engine Adapter Gasket 88
Engine Adapter, Pump Crankcase,
Spacer Plate and Head 88
Axial Cam Drive Components 88
Piston & Spring Assemblies 89
Unloader-Pressure Regulator Valve 90
Part 4 - Reassembly 91
Engine Adapter 91
Piston Oil Seals and Pistons 94
Spacer Plate 96
Pump Head Assembly 96
Pump Head Installation 98
Unloader-Pressure Regulator Valve 99
Main Component Assembly 99
Oil Fill 101
Part 5 - Troubleshooting 102
Glossary 105
TABLE OF CONTENTS
Table of Contents
Portable Pressure Washer Familiarization and Troubleshooting Guide

4
Table of Contents
Portable Pressure Washer Familiarization and Troubleshooting Guide

5
Operation of a pressure washer system may be briefly
described as follows. Please refer to Figure 1.1 for visual
component identification:
1. An inlet hose delivers water to the motor-driven, piston-
type pump. An inlet strainer (item 6) protects the pump
(item 5) against damage from solid impurities. The motor
driving the pump (item 9) may be gas or electric.
2. Rotary motion of the motor crankshaft is converted to
reciprocating motion of the pump’s pistons using an axial
cam.
On a piston’s ‘suction’ stroke, an inlet valve opens and
water is drawn into the piston chamber. On the piston’s
‘pressure’ stroke, that piston’s inlet check valve closes and
its outlet check valve is forced open so pressurized water
can leave the chamber. There is one inlet check valve and
one outlet check valve for each piston.
PRESSURE WASHER OPERATION
Section 1 • Operation
Pressure Washer Familiarization and Troubleshooting Guide
Item Name
1 Spray nozzle
2 Hi-Lo nozzle collar
3 Spray gun extension wand
4 Spray gun with locking trigger
5 Pump, including optional thermal relief and/or
easy start valve
Item Name
6 Inlet strainer
7 Unloader/pressure regulator valve
8 Chemical inject fitting (optional)
9 Engine on cart
10 High pressure hose
Figure 1.1 — Example Pressure Washer System

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3. The linear movement of the pistons pump a fixed volume
of water through the pressure washer system. The
volume of water flow depends on
a. piston diameter
b. length of piston stroke
c. number of pistons
d. number of piston strokes per minute.
4. The pressure that builds up in the system then depends
on the size of the spray nozzle orifice (item 1).
5. The fixed volume of water flows past an
unloader/pressure regulator valve (item 7), an optional
chemical injection assembly (item 8), through a high-
pressure hose (item 10), and to a spray gun (item 4).
6. The spray gun permits the operator to turn the flow of
water on or off.
7. If the water flow is turned off, water pressure within the
pump will increase until the unloader/regulator valve
(item 7) is moved off its seat. Flow is then bypassed back
to the pump inlet through an internal bypass channel.
Fluid bypass continues as long as the spray is turned off.
8. Recirculating bypass water can become hot enough to
damage seals and other pump parts. Some pressure
washer systems may be equipped with an internal thermal
relief valve which automatically replaces hot water with
cool water.
9. The optional chemical injection assembly (item 8) permits
detergents or other chemicals to be drawn into the water
stream and (along with the water) discharged from the
nozzle.
10. The nozzle collar (item 2), a part of the spray gun
nozzle, permits easy selection of high or low velocity
spray or a fan or stream spray pattern.
11. An optional easy start valve relieves pump outlet
pressure during cranking for quicker and easier starts.
12. As a nozzle is used, it often becomes clogged with
various types of matter. A clogged nozzle obstructs the
water flow causing a reduction in outlet pressure. It also
may cause the water stream to pulsate while the gun is
triggered. Therefore, the nozzle should be checked and
cleaned before every use, using the cleaning kit provided
with every Generac Portable Products®
pressure washer system.
13. The flow of water through the nozzle will gradually wear
away the nozzle orifice, causing the orifice to become
larger. This enlargement will eventually cause a reduction
in system pressure. For this reason, the nozzle should be
replaced periodically and always replaced with the
correct nozzle.
Section 1 • Operation
Portable Pressure Washer Familiarization and Troubleshooting Guide

7
Power Source
Generac Portable Products® uses several
engine manufacturers and different pump types on its
pressure washers. Generac Portable Products®
also uses an electric motor on some models.
The motor horsepower rating is designed into the overall
rating of the pressure washer. Pressure pumps require a
specified amount of horsepower for the pressure rating of
the pump. It is important to remember that engine
performance may be miss-diagnosed as a failed pump, and a
failed pump may also be miss-diagnosed as a faulty engine.
This manual does not cover service and repair of the engine.
Refer to the engine manufacturers’ service manual for engine
repair specifications.
Pressure washer pumps
Generac Portable Products® pressure washer
pumps are positive displacement, piston type pumps. They
use an axial cam to impart a reciprocating motion to its
three (3) pistons. The volume of water moved by the pump
depends on:
1. The axial distance each piston moves on its pressure
stroke
2. The diameter of each piston bore
3. The rotating speed of the axial cam (RPM of the engine or
electric motor)
4. The number of pistons
Theoretically, a pump will always move the same volume of
water, regardless of flow restrictions.
The pump’s axial cam is coupled to the engine crankshaft, so
that it revolves at the same speed as the engine. Figure 2.1
depicts a simplified cross-sectional diagram of a typical
pressure washer pump mechanism.
If the pump simply discharges water to atmosphere, no
pressure will be created. A pressure buildup in the system
occurs when flow is restricted downstream from the pump.
By adding a nozzle to the system, pressure will increase to
force the same volume of water through the nozzle orifice.
The smaller the nozzle orifice, the greater the pressure
needed to force the pumped volume through the nozzle.
PRESSURE WASHER COMPONENTS
Section 2 • Pressure Washer Components
Portable Pressure Washer Familiarization and Troubleshooting Guide
Figure 2.1 — Pressure Washer Pump
Item Name
1 Pressure adjust knob
2 Thermal bypass actuator
3 Inlet check valve
4 Garden hose connector/strainer
5 Thermal bypass outlet
6 Axial cam
7 Engine drive shaft
8 Engine adapter bearing assembly
9 Piston shoe bearing assembly
10 Piston spring retainer
11 Piston return spring
12 Piston
13 Outlet check valve
14 High pressure discharge port