National Mower 68 DL, 68 SR owner manual Trouble-Shooting, Situation Things To Check

Page 27

®

NATIONAL 68 SR & DL TRIPLEX

TROUBLE-SHOOTING

DANGER

All adjusting must be made with the engine off.

Do not do any investigation of the working parts of the machine with the motor running. Always turn the engine off!

Tractor Unit

 

Situation

Things To Check

 

 

 

 

 

 

Engine will not start

Turn ignition switch to on

 

 

Ensure that there is sufficient gasoline (petrol) in the tank

 

 

Make sure safety switches are making contact and mowing clutch is in

 

 

neutral

 

 

Look for a loose wire on ignition or spark plug wire not connected

 

 

Interlock system inoperative—check wiring, see "Electrical Diagrams"

 

 

Operator must be positioned on seat to depress safety switches

 

 

(Model 68 DL only)

 

 

 

 

 

Mower will not move

Differential gear selector must be in one of the drive positions

 

 

Engine drive clutch must be engaged

 

 

Drive belts too loose (see "Drive Belt Tension" in Maintenance section)

 

 

Visually check to see that pulleys are not slipping on shafts

 

 

If everything above is OK, check for a damaged gear(s) in the differential

 

 

gear box

 

 

 

 

 

Mower will not stop

Ensure that the main clutch is disengaged (brake will not stop engine)

 

 

Brake adjustment or service may be needed.

 

 

 

 

Cutting Units

Situation

Things To Check

 

 

Cutting units will not turn.

Clutches may not be engaged

 

Look for anything that could be jammed between the reel and the bed knife

 

Drive belts or drive chain may need tightening

 

Visually check that both the drive pulleys and the shafts are rotating

 

 

Cutting units turn but

Reel bed knife position may be out of adjustment (see "Reel to Bed Knife

will not cut

Adjustment" in Maintenance section)

 

Drive belts or drive chain may need adjustment.

 

Visually check that both the drive pulleys and the shafts are rotating

 

 

Cutting units will not stop

Disengage all clutches

turning

 

 

 

Uneven cut

Set height of cut to the same height on each cutting unit (see "Cutting Height

 

Adjustment" in Operation section of this manual.)

 

Check to see if any part is bent

 

Something may be jammed in cutting unit pivots and/or lift pivots, preventing

 

the cutting units from floating

 

 

68OM-06/03

27

Image 27 Contents
Model 68 SR Triplex Mower Model 68 DL Triplex Mower ONE Year Limited Warranty There is no Other Warranty Expressed or ImpliedNational Mower Company Introduction Table of ContentsOperation Safety InformationNational Mower Safe Operating Practices Training PreparationTraining MaintenanceISO Safe Operating Practices Hill OperationCalifornia Safe Operating Practices Maintenance and StorageMain Engine Clutch Lever Safety and Control DecalsSafety and Control Decals Height Adjuster Safety and Control Decals Uncrating Instructions Receipt of ShipmentAssembly SeatRear Cutting Unit Engine Reel to BED Knife AdjustmentRear Cutting Unit Belt National 68 SR & DL Triplex Wing Cutting UnitsPreparation OperationMain Clutch Lever Wing Cutting Unit Latch Rear Cutting Unit Lift Arm Seat Position Adjuster LeverTransport Clutch Model 68 DL only Rear Cutting Unit ClutchParking Brake Lever Safety SwitchesIgnition Switch Model 68 DL shown Service BrakeDIAL-A-HEIGHT Adjuster Optional Height of CUT AdjustmentOther Adjustments Standard AdjustersLubrication MaintenanceLubrication Points Maintenance Lubrication Points Brake Adjustment Reel AdjustmentsReel END Play Adjustment Height of CUT AdjustmentAdjusting Drive Belt Tension Main Drive Belt Tension Main Countershaft to Rear DriveRear Cutting Unit Drive Belt Tension Rear Cutting Unit Chain Tension BED Knife ReplacementGrinding Reels Back Lapping ProcedureIntroduction Recommended StepsMaintenance Record Situation Things To Check TROUBLE-SHOOTINGFrame & Running Gear Parts ListDescription Qty Rear Tire & Wheel AssemblyRunning Gear & MISC. Parts -- Model 68 DL Washer Seat Mounting & Belt GuardsDrive Mechanism -- Upper Portion Spring Drive Mechanism -- Middle Portion Drive Mechanism -- Lower Portion Drive Mechanism -- Model 68 DL Needle Bearing Rear Axle & Differential Shifter Lever Part No. Description QtyWing Cutting Units Roller Rear Cutting Unit Countershaft SKIDS, Reel END Shields & Guards Rollers & Standard Scrapers Description Qty. per Kit DIAL-A-HEIGHT Roller Scraper KIT, P/N 860033 includes itemsDIAL-A-HEIGHT Roller Adjuster KIT, P/N DIAL-A-HEIGHT ADJUSTER, P/N 205348 Response Safety SwitchesElectrical Diagrams Description Qty Model 68 SR Model 68 DL Electrical PARTS-- Models 68 SR & 68 DLSound & Vibration Levels SpecificationsMower Dimensions & Weight Engine Briggs & Stratton 138400 SeriesBelt CROSS-REFERENCE Chart Parts Ordering InformationFunction National Number Belt Mfr Number Déclaration DE Conformité Declaracion DE ConformidadConformiteitsverklaring Raymond Avenue Box Saint Paul, Minnesota Tel Fax