Pressure Washer Components; Power Source; Pressure Washer Pumps - Briggs & Stratton CE8070 Troubleshooting Manual

Portable Pressure Washer Familiarization and Troubleshooting Guide
Section 2 • Pressure Washer Components

PRESSURE WASHER COMPONENTS

Power Source

Generac Portable Products®
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®
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.
uses several
pressure washer
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.
7
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