Craftsman 917.27404 To Adjust Carburetor, Preliminary Setting, Final Setting, Acceleration Test

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TO ADJUST CARBURETOR

NOTE: The carburetor on this engine is low emission. It is equipped with an idle fuel adjusting needle with a limiter cap, which allows some adjustment within the limits allowed by the cap. Do not attempt to remove the limiter cap. The iimiter cap cannot be removed without breaking the adjusting needle.

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

In general, turning idle mixture valve in (clockwise) decreases the supply of fuel to the engine giving a leaner fuel/air mix- ture. Turning the idle mixture valve out

(counterclockwise) increases the supply

of fuel to the engine giving a richer fuel/air mixture.

mMPORTANT: Damage to the needle

valve and the seat in carburetor may result if screw is turned in too tight.

PRELIMINARY SETTING -

1.Air cleaner assembly must be assem- bled to the carburetor when making carburetor adjustments.

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

FINAL SETTING -

1.Start engine and allow to warm for five minutes. Make final adjustments with engine running and shift/motion control lever in neutral (N) position.

2.Move throttle control lever to slow posi- tion. With finger, rotate and hold throttle lever against idle speed screw. Turn idle speed screw to attain 1750 RPM.

3.While still holding throttle lever against

idle speed screw, turn idle mixture valve full travel clockwise then coun-

terclockwise until engine runs rough. Turn valve to a point midway between

those two positions. Release throttle lever.

ACCELERATION TEST -

4.Move throttle control lever from slow

to fast position. If engine hesitates or dies, turn idle mixture valve out (coun-

terclockwise) 1/8 turn. Repeat test and continue to adjust, if necessary, until engine accelerates smoothly.

High speed stop is factory adjusted. Do not adjust - damage may result. mMPORTANT: Never tamper with the engine governor, which is factory set for proper engine speed. Overspeed-

ing the engine above the factory high speed setting can be dangerous. If you

think the engine-governed high speed needs adjusting, contact a Sears or other qualified service center, which has proper equipment and experience to make any necessary adjustments.

/Throttle

Idle MixtureValve With Limiter

28

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Contents Rrftsmrn Limitedwarrantyon Craftsmanridingequipment Slope Operation Do not Ill.CHILDRENAcross Repair Protection Oil Drain Tube For Future Use Slope SheetHOW To SET UP Your Tractor Check BatteryAdjust Seat To Remove Tractor from Carton Unpack CartonALL Belts Check Deck LevelnessCheck Brake System Checkmst @@@@ Know Your Tractor STOPPmNG To Move Forward and BackwardTo Adjust Gauge Wheels To Stop Mower BladesTo Operate Mower To Operate on HillsADD Gasoune IientsTo Start Engine Purge TRANSMmSSmON Automatic Transmission Warm UPMulching Mowing Tips Before Each USE General RecommendationsOperator Presence System Blade CareBlade Removal To Sharpen BladeTo Clean Battery and Terminals Transaxle CooungTransaxle Pump Fluid BeltsTo Service PRE-CLEANER To Service CartridgeMuffler LNE Fuel FlterTractor To Remove MowerSIDE-TO-SIDE Adjustment with Bubble Level Alternate SIDE-TO-SIDE Adjustment MethodBelt Installation To Check and Adjust BrakeTo Adjust Brake LengthReplacement To Attach Jumper Cables Replacing BatteryTo Remove CABLES, Reverse Order To Adjust Throttle Control Cable To Replace Headught BulbTo Replace Fuse SemblyTo Adjust Carburetor Preliminary SettingFinal Setting Acceleration TestFuel System OtherProblem CausePower Problem CauseMower Biades wiii IHeadiights not working Iif so equipped CausecorrectionSlow Tractor ooMODEL Number SCHEItATmC Tractor o o Model Number KEY Part DESCRmPTmONTractor o o Model Number 917.274040 CHASSmS and Enclosures KEY Part Description Grounddrvf Tractor Model NumberTractor o o Model Number Ground DRmVE KEY PartTractor - Model Number 917.274040 STEERmNG Assembly Tractor o o Model Number 917.274040 STEERmNG Assembly Optional Equipment Tractor ooMODEL Number 917.274040 Seat Assembly Decals DescriptionTractor ooMODEL Number LmFTASSEfvIBLY 144 ,..4s Tractor - Model Number Mower DeckSTD 120 34X LO9 90O J57 \127 125 107 DESCRiPTiON 170351 Main Housing LO3 LssSlB 74I 20 @DESCRmPTmON Tractor ModelNumber 917.274040 BRmGGS ENGmNE=MODEL Number 407577,TYPESuggested Guide for Sighting Slopes for Safe Operation LE-FOYER Mc Rev 7.2.04 MH