Troy-Bilt 630B-Tuffy, 634F-Bronco, 634B-Super Bronco Checking And Adjusting, Engine, Maintenance

Section 5: Maintenance 19

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.

			c. Unhook the top of the spring from
			the Forward Clutch Bail.
			d. Use pliers to prevent the adjuster (B)
			from turning and turn the slotted
	ENGINE		screw located inside the spring
			clockwise (viewed from operator’s
			position) to increase tension on the
			spring. Turn the screw counter-
			clockwise to decrease tension. Once
		D	adjusted, reattach the spring to the
			Forward Clutch Bail.
			e. Repeat Steps 2 and 3 to re-measure
	C		the length of the spring. When the
			second measurement is between
			1/16" -to- 3/16" longer than the first
	A	E	measurement, retighten the hex nut
			(C) against the top of the adjuster (B).
		B	Replacement Belt Information
Figure 5-3: Install tines so that cutting edge of tines enter soil first when tiller moves forward.			If the drive belt needs to be replaced, see
			your local authorized dealer or refer to the
CHECKING AND ADJUSTING	measurement is between 1/16" -to- 3/16"
			Parts List for ordering information. Use
FORWARD DRIVE BELT TENSION	longer than the first measurement.		only a factory-authorized belt as an “over-
	4. If the spring is too short (less than		the-counter” belt may not perform satis-
It is important to maintain correct tension
			factorily. The procedure requires average
	1/16"), the tension is too loose. If the
on the forward drive belt. A loose belt will			mechanical ability and commonly available
	spring is too long (more than 3/16"), the
cause the tines and wheels to slow down –			tools.
	tension is too tight.
or stop completely – even though the
	5. To adjust the length of the spring:
engine is running at full speed. A too tight
belt can result in unintentional tine move-	a. Release the Forward Clutch Bail.
ment when the clutch bail is in the Neutral	b. Unthread the hex nut (C, Figure 5-4)
(released) position.	about halfway up the adjustment
• Check belt tension after the first two	screw (D).
hours of break-in operation and after			5
every 10 operating hours.
• At the end of each tilling season, check			4
the belt for cracks, cuts or frayed edges		3
and replace it as soon as possible.	A	2
To Check Forward Belt Tension:	C	1
1. Stop engine, wait for all parts to stop	B
moving and disconnect spark plug wire.		D
2. With the Forward Clutch Bail in an	Hold bail against handlebar while
open (released) position, measure and		taking second measurement of
note the overall length of the cable spring		spring
(A, Figure 5-4) by measuring from the out-
ermost coil to the outermost coil.

3.Squeeze the Forward Clutch Bail

against the handlebar (see Figure 5-4) and

re-measure the length of the coils. The	Figure 5-4: To check forward belt tension, take two measurements of
	the overall length of the coils in the spring – first with the clutch bail
belt tension is correct if this second
	open, then with the clutch bail closed against the handlebar.