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Petrol Powered Pole Tools

E&OE

Engine Tuning Guidelines

Running combustion engines in confined areas

CAN KILL IN MINUTES

. Engine exhaust

fumes contain carbon-monoxide – a deadly gas that you cannot smell or see. NEVER run

a combustion engine in confined areas EVEN IF windows and doors are open. ONLY run

combustion engines OUTDOORS and away from doors, windows and vents. • Petrol / fuel

/ gasoline is extremely flammable – keep clear of naked flames or other ignition sources. •

Do not have the engine running during inspection and maintenance unless specifically required. • The engine

should be cool enough to touch before performing maintenance activities. • Some maintenance activities

may be beyond the scope of some users. Do NOT attempt procedures that you are not comfortable with, or

do not have the necessary tools, experience or knowledge for – take the unit to an authorised service centre

or qualified technician for servicing. •

Failure to follow the maintenance schedule, using incorrect or

non-compatible accessories or replacements parts, or general negligence

may result in making the

product warranty void

. • Improper tuning can lead to engine failure –

engine failure due to improper

tuning is not covered under warranty

. • If you cannot tune the engine, contact an authorised service

centre for assistance or have the machine checked by a small engine specialist. • The carburettor is supplied

factory-set and should run properly. Engine tuning should be attempted only if the machine shows signs of

requiring adjustment. • A tachometer is recommended for setting engine idle and full throttle speeds.

The engine must be maintained in a reasonable "state of tune" to ensure best performance and safety. If the

engine is running roughly, emitting excessive smoke, not revving properly, not idling properly, showing signs

of reduced power, not responding crisply to the throttle etc, it may require "tuning". Before any engine tuning:

•

Service the

air filter

•

Service the

spark plug

•

Use fresh

fuel

2-Stroke Engine

Basic tuning for 2-stroke engines by owners is not difficult, however, care should be taken in understanding

the tuning process and learning how to recognise the symptoms for when engine tuning is required and

where and how to make adjustments. Note that factors such as altitude, fuel mixture, ambient temperature

etc may all affect engine running characteristics. There are two basic engine conditions that determine

improper tune:

•

Rich

- An adjustment that is too rich will cause the engine to smoke, have insufficient power, result in

additional carbon build up and may damage the engine. The proportion of fuel in the air/fuel mixture is so

high that the fuel does not burn well. The partially burned mixture is expelled into the exhaust and exits

the engine as smoke. Carbon build-up may affect the performance of the spark arrestor (if equipped) and

cylinder ports if run for a period of time. Outside of carburettor adjustments this can also be caused by

having too much oil mixed with the fuel, and/or old fuel.

•

Lean

- An adjustment that is too lean will also cause the engine to have insufficient power and is more

likely to damage the engine than a rich mixture. The proportion of fuel in the air/fuel mixture is so low that

there is not enough fuel to burn. Lean running causes the cylinder temperature to rise, which often leads

to engine seizure, and for excessive revving which may result in connecting rod bearing failure. Other

causes for a lean running condition include lack of oil in the fuel mix, and when the fuel tank runs empty.

Carburettor Adjustments

The carburettor has 2 adjustments available:

•

Idle Speed

– Controls how open the throttle is when released. If idle speed is too low, the engine may

stop when the throttle is released due to a lack of air/fuel mixture. If idle speed is too high, the engine

may idle at a speed that engages the clutch and cause the cutting attachment to rotate – this is a

dangerous condition that should never be allowed.

•

High Speed Mixture

– Controls the proportion of fuel in the air/fuel mixture at working speed. If the high

speed mixture is too rich, the engine may not reach the speed necessary for maximum power, emit

excessive smoke and respond poorly to throttle movement. If the high speed mixture is too lean, the