D. CARBURETOR
ADJUSTMENTS
YOUR
SEARS
PRODUCT
HAS BEEN
DESIGNED
AND
MANUFACTURED
TO SPECIFICATIONS
THAT
REDUCE
HARMFUL
EMISSIONS.
After
your unit
has been run for 5 hours,
the engine
has
broken-
in. To ensure
that your unit is at peak performance
and producing
the least amoUnt
of harm-
ful emissions
after
break-in,
have your SEARS
Service
Center/Department
adjust
your carburetor
for optimum
operating
conditions.
Properly
adjusting
the carburetor
is a complicated
task. Read all warnings
and instructions
thoroughly
before
starting
adjustments.
If you do not think
that you completely
understand
all warn-
ings
and instructions,
let your SEARS Service
Center/Department
perform
these
adjustments.
A WARN a
Make
carburetor
adjustments
with
the
lower
end sup]_orted
to prevent
the tri .n_. er line from
contacting
any object.
Hold tool w_th your hand;
do not use optional
shoulder
strap
for support,
i
A WARNn G
Keep others
away when
making
carburetor
ad-
ustments.
A WARNING
Serious
injury to the operator
and others
can oc-
cur if the carburetor
is not
properly
adjusted_
•
Poor
engine
performance
can be a result
of
other
causes
such
as dirty
air filter,
carbon
build-up
on
muffler
outlets,
etc.
See
"Trouble
Shooting
Ch_ct _ before
proceed-
mg with
carburetor
adjustments.
•
For best results,
it is recommended
that you
have
your
SEARS
Ser-Ace
Center/Depart-
ment
make
all carburetor
adjustments.
Your
dealer has the training, experience,
and tools nee-
essary to properly adjust
your unit to meet
our
factory
performance
spe_Cications.
This service
is not covered by warranty.
If it becomes necessary
for you to make carburetor
adjustments
yotLrself,
follow the described procedures very carefiflly.
•
Very small
adjustments
can
affect
engine
performance.
It is important to turn the screw a
very small amount
per adjustment
and test per-
formance
before
making
further
adjustments.
Each adjustment
shouldbe
no more than the
width of the slot in the adjusting
screw.
•
This
is a complicated
task
and it is impor.
taut
to follow
instructions
in sequence
as
indicated.
Ie
TROUBLE
SHOOTING
SUGGESTIONS
-
Eng_me will not continue
to run at idle posi-
tion, See "Idle Speed Adjustment"
and "Mix-
ture Adjustment."
-
Engine dies or hesitates
when
it should accel-
erate. See 'Tkcceleration
Check."
-
Loss of cutting
power
which
cannot
be cor-
rected by cleaning
the air filter. See "Mixture
Adjustment."
-
Engine
does not return
to idle from full throt-
tle within 2 seconds.See
"Deceleration
CheCk."
-
Engine, will not run.
See "Trouble
Shooting
Chart.
Then, ff carburetor
requires
adjust-
ment, begin with "Basic Carburetor
Settings."
l
A
.
J
The
trimmer
line
will be sp'.mning during
this]
procedure.
Wear your protective
eqmpment
and |
observe
all safety
instructions.
I
2. BASIC CARBURETOR
SETrINGS
In most cases, your engine can be made to
run properly with minor carburetor adjustments.
Refer to "Trouble Shooting Suggestions,
for con-
dition you are experiencing;
follow instructions.
Basic carburetor settings are provided below.
•
Turn the mixture
screw (Figure 21 ) to the
midpoint.
Do not attempt to adjust
the screw
beyond the stops as damage can occur.
3. ADJUSTING
PROCEDURE
a, PREPARATION
L Use fresh fuel mix (see fueling section).
2. Make sure the line extends to the length al-
lowed by the line limiter to provide correct
load on engine.
3. Start the engine. Cut grass for 3 minutes to
warm engine. The engine must be at operat-
ing temperature
before carburetor
adjust-
rnents can be performed
correctly.
b. IDLE
SPEED
ADJUSTMENT
1. Allow engineto
idle. Be sure the trimmer
line is extended
to the maximum
length
al-
lowed by the line limiter.
2. Adjust
idle speed
screw (Figure 21 ) until
engine continues
to run without
staIlhag.
- Turn screw clockwise to increase engine
speed
if the engine stalls or dies.
- Turn screw counterclockwise
to slow en-
_in_ dowm
3. Follow
instructions
in
'_cceleration
Check" and "Deceleration
Check."
4. No fizrther
adjustments
are necessary
if
._ is satisfacto_
..........
Mixture
Screw
(with Limlter Cap;
Air Filter
Cover
Idle Speed Screw
Figure
21
- 16-