Troy-Bilt 640C-Tuffy Tiller User Manual


 
20
FORWARD CLUTCH
BAIL ADJUSTMENT
If the Forward Clutch Bail does not func-
tion properly, first check that the forward
drive belt is adjusted properly (see Check-
ing and Adjusting Forward Drive Belt Ten-
sion). If this fails to correct the problem,
contact Troy-Bilt LLC or your authorized
dealer for service advice.
CHECKING AND ADJUSTING RE-
VERSE DRIVE BELT TENSION
(Model 644A only)
It is important to maintain correct tension
on the reverse drive belt. A loose belt will
cause the tines and wheels to slow down –
or stop completely – even though the en-
gine is running at full speed.
When checking belt tension, also check the
belt for cracks, cuts or frayed edges and
replace it as soon as possible.
• Check belt tension after the first two
hours of break-in operation and after every
10 operating hours.
To Check Reverse Belt Tension:
1. Stop engine, wait for all parts to stop
moving and disconnect spark plug wire.
2. Remove screw in plastic belt cover and
slide belt cover (which is attached to for-
ward clutch cable) out of the way.
3. Have an assistant pull the Reverse
Clutch Control knob all the way out and
hold it in that position. Measure the length
of the cable wire between the end of the
threaded cable adjuster (A, Figure 5-5) and
the end of the Z-fitting (B) to which the ca-
ble wire is attached.
4. The belt tension is ideal if the cable wire
length measures between 1/8" to 1/4". If it is
less than 1/8" (and if there is no reverse ac-
tion when the tiller is running), then make
the following adjustments
NOTE: If the length is more than 1/4", no ad-
justment is needed—as long as the reverse
action functions properly.
5. Release the Reverse Clutch Control
knob.and then unthread the inner jam nut
(C, Figure 5-6) one to two turns. Pull the
threaded cable adjuster (A, Figure 5-6) to
the left until the inner jam nut (C) touches
the bracket.
6. Prevent the inner jam nut (C) from turn-
ing and tighten the outer jam nut (D)
against the bracket. Prevent the outer jam
nut (D) from turning and tighten the inner
jam nut (C) against the bracket.
7. Measure the gap by repeating Step 3.
Readjust as needed by repeating Steps 5
and 6.
8. Reinstall the belt cover.
Replacement Belt Information
If the drive belt needs to be replaced, see
your local authorized dealer or refer to the
Parts List for ordering information. Use
only a factory-authorized belt as an “over-
the-counter” belt may not perform satis-
factorily. The procedure requires average
mechanical ability and commonly available
tools.
ENGINE CLEANING
Keeping the engine clean will help to en-
sure smooth operation and prevent dam-
age from overheating. Refer to the Engine
Owner’s Manual for engine cleaning ser-
vice intervals and instructions. Be sure
that the muffler is cool before servicing the
engine.
AIR CLEANER SERVICE
The air cleaner filters dirt and dust out of
the air before it enters the carburetor. Op-
erating the engine with a dirty, clogged air
filter can cause poor performance and
damage to the engine. Never operate the
engine without the air cleaner installed. In-
spect and service the air cleaner more of-
ten if operating in very dusty or dirty
conditions. Refer to the engine Owner’s
Manual for air cleaner service intervals and
instructions.
ENGINE OIL SERVICE
Check the engine oil level before each use
and after every five hours of continuous
operation. Running the engine when it is
low on oil will quickly ruin the engine.
It is recommended that you change the
motor oil after every 10 hours of operation
and even sooner when operating in ex-
tremely dirty or dusty conditions. Refer to
the Engine Owner’s Manual for detailed
service instructions.
A. To Check the Engine Oil Level:
1. Park the tiller on a level area and shut off
the engine.
2. Level the engine (use the Depth Regula-
tor Lever to adjust the engine angle).
Figure 5-5: Measure cable wire length to
check for correct reverse belt tension.
D
Figure 5-6: Move threaded adjuster (A) to left
to increase belt tension.
C
A
WARNING: Before inspecting, cleaning or servicing the machine, shut off engine, wait for all
moving parts to come to a complete stop, disconnect spark plug wire and move wire away from
spark plug. Failure to follow these instructions can result in serious personal injury or property
damage.
A B