Troy-Bild TB415CS Manual Del Operador página 11

CARBURETOR ADJUSTMENT
WARNING:
The cutting attachment may spin during idle
speed adjustments. Wear protective clothing and observe all
safety instructions to prevent serious personal injury.
The idle speed of the engine is
adjustable. An idle adjustment screw
is reached though a hole in the top of
the engine cover (Fig. 29).
NOTE: Careless adjustments can
seriously damage your unit.
An authorized service dealer
should make carburetor
adjustments.
Check Fuel
Old fuel is usually the reason for
improper unit performance. Drain
and refill the tank with fresh fuel prior
to making any adjustments. Refer to
Oil and Fuel Information.
Clean Air Filter
The condition of the air filter is important to the operation of the unit.
A dirty air filter will restrict air flow. This is often mistaken for an out
of adjustment carburetor. Check the condition of the air filter before
adjusting the idle speed screw. Refer to Air Filter Maintenance.
Adjust Idle Speed Screw
If, after checking the fuel and cleaning the air filter, the engine still
will not idle, adjust the idle speed screw as follows:
1. Start the engine and let it run at a high idle for a minute to warm
up. Refer to Starting/Stopping Instructions.
2. Release the throttle trigger and let the engine idle. If the engine stops,
insert a small phillips or flat blade screwdriver into the hole in the air
filter/muffler cover (Fig. 29). Turn the idle speed screw in, clockwise,
1/8 of a turn at a time (as needed) until the engine idles smoothly.
Checking the fuel, cleaning the air filter, and adjusting the idle speed
should solve most engine problems. If not and all of the following are true:
• the engine will not idle
• the engine hesitates or stalls on acceleration
• there is a loss of engine power
Have the carburetor adjusted by an authorized service dealer.
ROCKER ARM CLEARANCE
WARNING:
To prevent serious personal injury, make
sure the cutting attachment has stopped rotating before
you turn it off and set it down.
This requires disassembly of the engine. If you feel unsure or unqualified
to perform this, take the unit to an authorized service center.
NOTE: Inspect the valve to rocker arm clearance with a feeler
gauge after the first 10 hours of operation and then every
25 hours of operation thereafter.
• The engine must be cold when checking or adjusting the valve
clearance.
• This task should be performed inside, in a clean, dust free area.
1. Remove the muffler cover by pressing down on it, separating it
from the engine cover. Using a flat blade screwdriver,
disengage the middle and front tabs and slots first. The cover
will hinge off from the rear tab (Fig. 30).
2. Remove the two (2) screws on top of the engine cover with a
Flat-head or T-25 Torx screwdriver (Fig. 31).
3. Remove the screw behind the engine cover (Fig. 32).
4. Disconnect the spark plug wire.
5. Clean dirt from around the spark plug. Remove the spark plug from
the cylinder head by turning a 5/8 in. socket counterclockwise.
6. Remove the engine cover (Fig. 31).
7. Clean dirt from around the rocker arm cover. Remove the screw
holding the rocker arm cover with a large flat blade screwdriver or
Torx T-25 bit (Fig. 33). Remove the rocker arm cover and gasket.
8. Pull the starter rope slowly to bring the piston to the top of its
travel, (known as top dead center). Check that:
• The piston is at the top of its travel while looking in the spark
plug hole (Fig. 33)
MAINTENANCE AND REPAIR INSTRUCTIONS
Idle Adjustment Screw
Fig. 29
11
Engine Cover
Rear Slot
and Tab
Middle Tab
Middle Slot
Top View Of The Engine
Engine Cover
Screw
Fig. 32
• Both rocker arms move freely, and both valves are closed
If these statements are not true, repeat this step.
9. Slide the feeler gauge between the rocker arm and the valve return
spring. Measure the clear-ance between the valve stem and rocker
arm (Fig. 34). Measure both the intake and exhaust valves.
Rocker Arms
INTAKE
Feeler Gauge
Front Tab
Front Slot
Fig. 30
Remove Screws
Muffler
Fig. 31
Rocker
Arm
Cover
Spark
Plug
Hole
Fig. 33
Adjusting Nuts
EXHAUST
Fig. 34