Maintenance; General; Carburetor Adjustment; Checking, Maintaining And Servicing Chain Saw Safety Equipment - MTD 450E Operator's Manual

MAINTENANCE
General
The user must only carry out the maintenance and
service work described in this manual. More extensive
work must be carried out by an authorised service
workshop.
Carburetor adjustment
Your Husqvarna product has been designed and
manufactured to specifications that reduce harmful
emissions.
Function
The carburetor governs the engine's speed via the
throttle control. Air and fuel are mixed in the
carburetor. The air/fuel mixture is adjustable. Correct
adjustment is essential to get the best performance
from the machine.
The T-screw regulates the throttle setting at idle
speed. If the T-screw is turned clockwise this gives a
higher idle speed; turning it anti-clockwise gives a
lower idle speed.
Basic settings and running in
The basic carburetor settings are adjusted during testing
at the factory. Fine adjustment should be carried out by a
skilled technician.
Rec. idle speed: See the Technical data section.
Fine adjustment of the idling speed T
Adjust the idle speed with the T-screw. If it is necessary to
re-adjust, turn the T-screw clockwise while the engine is
running, until the chain starts to rotate.Then turn counter-
clockwise until the chain stops. A correctly adjusted idle
speed setting occurs when the engine runs smoothly in
every position. It should also be good margin to the rpm
when the chain starts to rotate.
| _ adjusted so that the chain stops at idle.
| De not use the chain saw until it has
b_ adjusted or repaired.
Correctly adjusted carburetor
When the carburetor is correctly adjusted the machine
accelerates without hesitation and the machine 4-cycles a
little at max. speed. It is also important that the chain does
not rotate at idle. If the L-jet is set too lean it may cause
starting difficulties and poor acceleration. If the H-jet is set
too lean the machine will have less power, poor
acceleration and could suffer damage to the engine.
Checking, maintaining and
servicing chain saw safety
equipment
contact our servicing dealer.
Chain brake and front hand guard
Checking brake band wear
Brush off any wood dust, resin and dirt from the chain
brake and clutch drum. Dirt and wear can impair operation
of the brake.
Regularly check that the brake band is at least 0.024 inch
(0.6 mm) thick at its thinnest point.
Checking the front hand guard
Make sure the front hand guard is not damaged and that
there are no visible defects such as cracks.
Move the front hand guard forwards and back to make
sure it moves freely and that it is securely anchored to the
clutch cover.
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