Starter Unit; Engine; Spark Plug; Spark Arresting Muffler - Efco MT 3700 Operator's Instruction Manual

MAINTENANCE

Starter Unit

Use a brush to keep the cooling vents of the starter assembly free
and clean of debris (Fig. 90).
WARNING: The coil spring is under tension and
could fly apart causing serious injuries. Never try to
disassembly or modify it.
90

Engine

Clean the cylinder & flywheel fins with compressed air or a brush
periodically (Fig. 91). Dangerous overheating of engine may occur
due to impurities on the cylinder.
WARNING: Never run the saw without all the parts,
including the drivecase cover and starting housing,
securely in place.
Because parts can fracture and pose a danger of
thrown objects, leave repairs to the flywheel and
clutch to trained Servicing Dealers.
91

Spark Plug

This engine uses a NGK BPMR6A with .02" (0.5 mm) electrode gap
(Fig. 92). Use an exact replacement and replace every six months
or more frequently, if necessary.
WARNING: Never test the ignition system with igni-
tion wire connector removed from spark plug or with
unseated spark plug, since uncontained sparking
may cause a fire. A loose connection between spark
plug terminal and ignition wire connector in the boot
may create arcing that could ignite combustible
fumes and cause a fire.
92
Use only resistor type spark plugs of the approved range.
Factors such as:
- too much oil in fuel mix;
- dirty air filter;
- unfavourable running conditions, e.g. operating at part load;
may result in rapid deterioration of the spark plug.

Spark Arresting Muffler

The chainsaw is provided with a Spark Arrester System p.n.
50170191 (Fig. 93) complying with the requirements of SAE J335
93
standard; you can check the p.n. of the Spark Arrester System on
the muffler itself.
WARNING: A faulty or altered spark arrester system
screen can create a fire hazard.
Through normal use the screen can become dirty and should be
inspected weekly and cleaned as required.
To clean:
• Allow the muffler to cool.
• Remove the three (3) muffler screws (B).
en
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