National Mower 68 SR Lawn Mower User Manual


 
NATIONAL 68 SR & DL TRIPLEX
®
27
68OM-06/03
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 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
Cutting Units
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!
Situation Things To Check
Tractor Unit
TROUBLE-SHOOTING
Situation
Things To Check
DANGER