STEP 4: INSTALL FORWARD CLUTCH CABLE

1.Carefully unwrap the forward clutch cable (cable without an attached knob) from its shipping position and slide the thin cable wire (M, Fig. 2-4) into the slot in the cable bracket. Push the cable connector (N, Fig. 2-4) up through the hole in the bracket until the groove in the connector snaps into place.

2.Thread the #10-24 hex nut (Z, Fig.

2-5) halfway onto the screw (V) which runs through the spring (W, Fig. 2-5).

3.Thread the screw (V) into the cable adjuster (X).

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Fig. 2-4: Installing forward clutch cable bracket and cable.

2

Assembly

NOTE: Incorrect

4.Check for correct tension on the forward drive belt by taking two measurements of the cable spring, as follows:

a.With the Forward Clutch Bail (Y, Fig. 2-6) in an open (released) position, measure the length of the cable spring (W) from the outermost coil to the outermost coil.

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Fig. 2-5: Cable

Fig. 2-6: Attach forward

spring and

 

clutch cable spring to

adjuster.

 

forward clutch bail.

b.Squeeze the Forward Clutch Bail against the handlebar (see Fig. 2-7) and re-measure the spring length. The belt tension is correct if this second measurement is between 1/16” to 3/16” longer than the first measurement. If so, turn the hex nut (Z, Fig. 2-7) tightly against the cable adjuster (X) while preventing the cable adjuster from turning.

c.If the spring length is incorrect, you must adjust the cable tension as described in Checking and Adjusting Forward Drive Belt Tension in Section 5. Incorrect cable tension can result in belt slippage (cable tension too loose), or unintentional tine movement when the clutch bail is in Neutral (cable tension too tight).

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Fig. 2-7 :To check forward belt tension, take two measure- ments of the length of the coils in the spring — first with the bail open, then with the bail held against the handle- bar.

STEP 5: INSTALL REVERSE CLUTCH CABLE (MODELS 643B AND 645A ONLY)

1.Unwrap the reverse clutch cable (CC, Fig. 2-8 and Fig. 2-9) from its shipping position and route it up to the handlebar. Be sure that the cable is routed beneath the Forward Clutch Bail.

2.Insert the cable (CC, Fig. 2-8) through the slot in the cable bracket and position the flat side of the threaded assembly next to the flat side of the hole. Slide the hex nut (DD) up the cable and tighten it securely.

3.Fasten the reverse clutch cable to the left side handlebar with a cable tie (EE, Fig. 2-9).

4.Test the function of the reverse clutch by pulling out and releasing the cable knob. The knob should return to its neutral position (resting against bracket). If it doesn’t, contact your local dealer.

cable tension can result in belt slippage (cable tension too loose), or unintentional tine movement when the clutch bail is in Neutral (cable tension too tight).

7

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Image 7
Bolens 643C Install Forward Clutch Cable, Thread the #10-24 hex nut Z, Fig, Thread the screw V into the cable adjuster
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643B, 643C, 645A specifications

The Bolens 645A, 643C, and 643B are celebrated models in the lineup of Bolens garden tractors, known for their durability and versatility. These machines, produced during the 1970s and 1980s, are vintage favorites for homeowners and garden enthusiasts seeking rugged equipment for their gardening needs.

The Bolens 645A is especially noted for its robust build and powerful performance. Equipped with a 7-horsepower engine, the 645A can tackle a variety of tasks, from mowing to snow removal, making it a multipurpose tool in any garden or landscape. One of the main features of the 645A is its hydrostatic transmission, which allows for seamless speed adjustments, providing exceptional maneuverability in tight spaces and varied terrain.

Similarly, the Bolens 643C and 643B models boast impressive features and capabilities. The 643C is renowned for its compact yet powerful 6-horsepower engine. It includes a gear-driven transmission, which offers reliable power transfer and increased efficiency while operating under demanding conditions. The steady performance of the 643C makes it ideal for smaller properties, where precision and control are paramount.

The 643B, while slightly less powerful than its sibling, still holds its own with a solid 5-horsepower engine. It is particularly favored for its ease of use and relatively low maintenance requirements, making it a perfect choice for casual gardeners or those new to the world of garden tractors. Its straightforward controls and simple mechanisms ensure that users can quickly learn to operate it proficiently.

All three models are engineered with a focus on user comfort. The seating is designed ergonomically, allowing users to operate for extended periods without discomfort. Additionally, the accessibility for maintenance tasks is a notable characteristic, ensuring that both professional and amateur gardeners can perform regular upkeep with ease.

In terms of technology, these models utilize straightforward mechanical designs with minimal electronic components, which reduces the likelihood of breakdowns and simplifies repairs. The rugged construction of the chassis and attachments demonstrates Bolens' commitment to longevity and resilience, making these tractors a solid investment for any gardening enthusiast.

In summary, the Bolens 645A, 643C, and 643B models stand out in the garden tractor market due to their powerful engines, user-friendly designs, and robust construction. They represent a blend of efficiency and reliability, catering to a wide range of gardening tasks and maintaining a loyal following among vintage equipment enthusiasts.
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