Rear Cutting Unit Chain Tension

MAINTENANCE

A chain drive is located on the left side of the rear cutting unit. It maybe helpful to remove the Chain Shield (A) prior to adjusting the chain tension.

Adjust the tension of the chain by loosening the 4 bolts (B) on the rear cutting unit countershaft housing. Rotate the countershaft housing (C) about the pivot line created by the fixed bolts. The slots on the countershaft housing will slide over the remaining two bolts. Rotate the countershaft housing until proper chain tension is achieved. Tighten bolts.

Proper tension is achieved when the chain is slightly loose, but does not deflect more than 1/2" when pressed in the middle of the span between the two sprockets.

BED KNIFE REPLACEMENT

		Reels and bed knife are sharp. Wear
	DANGER	Reels and bed knife are sharp. Wear
	DANGER	gloves to avoid cutting fingers on
		gloves to avoid cutting fingers on
		sharp edges. Wear safety glasses
		to protect eyes.

When the bed knife becomes damaged or too worn to keep sharp, it must be replaced. Follow the procedure below.

1.The backbar (A), bed knife (B) and fasteners (C,D) have been assembled at the factory under tension. To ease replacement and prevent misalignment of compo- nents, you may wish to clamp the leading edge of the backbar in two or three places before removing the old fasteners.

2.Remove the old shoulder nuts (C) and flat head screws

(D). If shoulder nuts are badly rusted or corroded, they may have to be cut off and screws driven out to be removed.

3.Clean the bottom surface of the backbar for maximum metal contact with the new bed bar.

4.Fasten the new bed knife to the bottom of the backbar in the position shown (bent edge up). Shoulder of shoulder nuts (C) must be seated firmly in the backbar and screws (D) must be flush with the bottom of the bed knife.

5.Torque shoulder nuts 35 to 40 ft-lbs.

24	68OM-06/03

68 SR, 68 DL specifications

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