Sears 917.25559 manual To Adjust Carburetor See Fig, Final Setting, Acceleration Test

Page 24

SERVICE AN ADJUSTMENTS

ENGINE

..... i TO ADJUST THROTTLE CONTROL CABLE

(See Fig. 33)

The throttle control has been preset at the factory and adjustment should not be necessary, Check adjustment as described below before loosening cable, tf adjustment is necessary, proceed as follows:

•With engine not running, move throttle control lever

from "SLOW" to "CHOKE" position. Slowly move lever from "CHOKE" to "FAST" position.

oCheck that holes "A" in governor control lever and hole in governor plate line-up, If holes "A" are not aligned, Ioosen clamp screwand move throttle cable until holes are aligned. Tighten clamp screw securely,

GOVERNOR

GOVERNOR

CONTROL LEVER

CONTROL PLATE

 

HOLES "A"

CLAMP

THROTTLE

 

SCREW

 

CABLE

FINAL SETTING -

•Start engine and allow to warm for five minutes. Make finat adjustments with engine running and shift/motion contro! lever in "NEUTRAL" position.

•Move throttle control lever to "SLOW" position. With

finger, rotate and hold throttle lever against idle speed screw. Turn idle speed screw to attain 1750 RPM.

•While still holding throttle lever against idle speed screw, turn idle mixture valve in (clockwise) until en- gine begins to die and then turn out (counterclockwise) until engine runs rough. Turn valve to a point midway between those two positions. Release throttle Jever.

ACCELERATION TEST -

"Move throttle control lever from "SLOW" to "FAST"

position. If engine hesitates or dies, turn idle mixture valve out (counterclockwise) 1/8 turn. Repeat test and continue to adjust, if necessary, until engine acceler- ates smoothly.

High speed stop is factory adjusted. Do not adjust - damage may result.

iMPORTANT: NEVER TAMPER WtTH THE ENGINE GOVERNOR, WHICH IS FACTORY SET FOR PROPER

ENGINE SPEED. OVERSPEEDtNG THE ENGINE ABOVE

THE FACTORY HIGH SPEED SETTING CAN BE

DANGEROUS. iF YOU THINK THE ENGINE-GOVERNED

HIGH SPEED NEEDS ADJUSTING, CONTACT YOUR NEAREST AUTHORIZED SERVICE CENTER, WHICH HAS PROPER EQUIPMENT AND EXPERIENCE TO MAKE ANY NECESSARY ADJUSTMENTS.

FIG, 33

THROTTLE

IDLE SPEED

LEVER

SCREW

TO ADJUST CARBURETOR (See Fig. 34)

The carburetor has been preset at the factory and adjust- ment should not be necessary. However, minor adjust- ment may be required to compensate for differences in fuel, temperature, altitude or load. If the carburetor does need adjustment, proceed as follows:

tn general, turning idfe mixture valve in (clockwise) de- creases the supply of fuel to the engine giving a leaner fuel/ air mixture. Turning the idle mixture valve out (counter-

clockwise) increases the supply of fuel to the engine giving a richer fuel/air mixture.

iMPORTANT: DAMAGE TO THE NEEDLE VALVE AND

TH E SEAT IN CARBURETOR MAY RESULT IF SCREW IS TURNED tN TOO TIGHT.

PRELIMINARY SETTING

•Air cleaner assembly must be assembled tothe carbu- retor when making carburetor adjustments.

,Be sure the throttle control cable is adjusted properly (see above).

•With engine off turn idle mixture valve in (clockwise) closing it finger tight and then turn out (counterclock- wise) I full turn.

IDLE MIXTURE

VALVE

FIG. 34

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Contents Owners Manual Model no IV. Service Safe Operation Practices for RideOn MowersI1. Slope Operation ChildrenMawntenance Agreement RaND Accessories AN Attachments Engine NantenancePerformance Contents of Hardwa Pack Tools Required For Assembly To Remove Unit from CartonUnpack Carton Attach STEE!RJNG Wheel See FigAdjustmentlock Washer Bolt Nstall Seat See FigCheck Tire Pressure Check Deck LevelnessASS LY CheckmstOperation NOW Your TractorHOW to USE Your Tractor To Adjust Mower Cutting HIT l,,= FigTo SET Parking Brake See Fig To USE Throttle Control See FigOpefiatio Before Starting the EngineTo Operate on Hills To TransportOperatio Mowing TipsMaintenance Schedule ChartCustom Espo General RecommendationsTractor Brake OperationTires Blade CareTransaxle Pump Fluud Level See Figs, t3 Transaxle CooungCusto E Responsi ClsaningMuffler Spark PlugsErvice AN Adjustm TS To Removemower See FigService AN Adjustments To Level Mower HousingService AN AdjustmentsTo Adjust Brake See Fig, ,!5 To Replace Mower Blade Drive Belt Service AN Adjustments To Adjust Motion Control Lever Connector Forward AdjustmentTo Start Engine WiTH a Weak Battery Front Wheel TOE-IN/CAMBERTo Remove Wheel for Repairs See Fig To Attach Jumper CablesService ITO Replace Fuse See FigTo Replace Headlight Bulb To Adjust Carburetor See Fig Final SettingPreliminary Setting Acceleration TestStorage EngineFuel System Engine OILProblem Cause CorrectionProblem Cause Correction Trou Leshooti G PointsWiring Insulated Clips NON-REMOVABLE Connections Fuse 3OAMPSolenoid Pedal UP CLUTCH/BRAKEDecals Wheels and TiresKEY Part Description NO. no KEYRepair Parts KEY Part Standard Hardware -- Purchase LocallyRepair Parts Chassb and Enclosures 12.5 HP 38 Riding Lawn Tractor -MODEL Number 917,255590 Drhve KEY Part DescriptionStandard Hardware Locally3543 2324 12.5 HP 38 Riding Lawn Tractor =.. Model Number 917,255590 KEY PartDescription EQU1PM ENT KEY Part DescriptionStandard Hardware - Purchase Locally 12.5 HP 38 Riding Lawn Tractor == Model Number 917,255590 KEY Part NO. no KEY Part DescriptionSeat Assem BLY KEY Part NO. no DescriptionSection Repair Parts 12.5 HP 38 R DtNG Lawn Tractor = Model Number 9!7o255590 Descrbption837 GasketsetSpecial Tools Required to NSTALLo 13114 125KEY Number ManufacturerKEY Part Dsscription 005Part NO. no Suggested Guide for SiGHTiNG Slopes for Safe Operation Mowe Automatic HydrostaticLAW Tractor Part Description
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