MTD 643 - Manual (Page 13)

13
Traction Control / Auger Control Lock
The cams on the ends of the control rods which
interlock the traction drive and auger drive controls
must be lubricated at least once a season or every 25
hours of operation. The cams can be accessed beneath
the handle panel. Use a multi-purpose automotive
grease.
Drive and Shifting Mechanism
Lubricate at least once a season or after every 25 hours
of operation. Remove the rear cover, lubricate any
chains, sprockets, gears, bearings, shafts, and shifting
mechanism at least once a season. Use engine oil or a
spray lubricant. Avoid getting oil on the friction
wheel rubber and aluminum drive plate. Refer to
Figure 9.
There is a grease fitting on the top of the axle shaft
which drives the rear track drive wheels on both sides
of the unit. Grease these fittings every 25 hours or once
a season.
SECTION 7: SERVICING YOUR SNOW THROWER
WARNING: Before servicing, repairing, or
inspecting, disengage all clutch levers and
stop engine. Wait until all moving parts
have come to a complete stop. Disconnect
spark plug wire and ground it against the
engine to prevent unintended starting.
Engine
Refer to the separate engine manual packed with your
unit for all engine maintenance procedures.
Augers
• The augers are secured to the spiral shaft with two
shear bolts and hex lock nuts. If you hit a hard
foreign object or ice jam, the snow thrower is
designed so that the bolts may shear.
Refer to Figure 14.
• If the augers will not turn, check to see if the bolts
have sheared. Replacement shear bolts and hex
lock nuts have been provided with the snow
thrower. When replacing bolts, spray an oil
lubricant into shaft before inserting new bolts.
IMPORTANT: NEVER replace the auger shear bolts with
standard hex bolts. Any damage to the auger gearbox
or other components as a result of doing so will NOT be
covered by your snow thrower’s warranty.
Shave Plate and Skid Shoes
• The shave plate and skid shoes on the bottom of
the snow thrower are subject to wear. They should
be checked periodically and replaced when
necessary.
• To remove skid shoes, remove the four carriage
bolts, cupped washers and hex nuts which attach
them to the snow thrower. Reassemble new skid
shoes with the four carriage bolts, cupped washers
(cupped side goes against skid shoes) and hex
nuts. See Figure 15.
Figure 15
Belt Removal And Replacement
Auger Belts
NOTE: It is necessary to remove both belts in order to
change either one. If changing just one belt, be certain
to check the condition of the other belt.
• Remove the plastic belt cover at the front of the
engine by removing the two self-tapping screws.
See Figure 16.
Figure 16
Carriage Skid Shoe
Hex Nuts
Shave Plate
Bolts
Skid Shoe
Self-Tapping
Screw
Belt Cover