LiftMaster PREMIUM Serie Mode D'emploi page 6

Assembly
2 Tighten the Chain
1. Loosen the inner nut and lock washer on the trolley threaded shaft.
2. Tighten the outer nut until the chain is a 1/2 inch above the base of the rail at the midpoint of
the rail.
3. Re-tighten the inner nut.
Slack in the chain is normal when the door is closed. No readjustment is necessary.
Sprocket noise can result if the chain is too loose. During future maintenance, ALWAYS pull the
emergency release handle to disconnect the trolley before adjusting the chain.
1/2" (13 mm)
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