blade belt does not engage,motor still runs

william harris,:"TO REPLACE MOWER BLADE DRIVE BELT (See Fig. 34)

Park the tractor on level surfaCe Engage parking brake. For assistance, there is a belt installation guide decal on the underside of mower belt cover.

Remove mower (See "TO REMOVE MOWER" in this section of this manual).

Remove screws and idler arm nut securing mower belt cover and remove cover

Roll belt over the top of the R,H. mandrel

Pull belt off all other mandrels,

Remove any dirt and grass which may have accumulated mandrels or idler arm.

Check deck idler arm assembly and flat idler to see that they rotate freely.

Be sure spring is hooked in deck idler arm assembly and on bolt in mower housing,

Install new belt in groove of LH mandrel pulley, lower groove of center mandrel pulley and around flat idler as shown.

From a position at discharge end of mower, roll idler belt into groove of RH mandrel pulley.

Rotate center mandrel pulley by hand to make sure belt is in grooves properly.

Reassemble top cover to deck. Tighten all screws and idler arm nut securely,

Install mower to tractor manual."

Download the manual from here, page 21 will guide you. Hope this helps, good luck.