Chamberlain 2500B - Manual (Page 23)

ALL ONE-PIECE DOORS
1. Assemble the Door Arm:
• Fasten the straight and curved door arm sections
together to the longest possible length (with a 2
or 3 hole overlap).
• Make sure the garage door is fully closed.
Connect the straight door arm section to the door
bracket with the 5/16"x1-1/4" clevis pin.
• Secure with a ring fastener.
• Pull the emergency release handle,
disconnecting the outer trolley from the inner
trolley by pulling straight down on the emergency
release handle and sliding the outer trolley back
toward the motor unit.
• Connect the curved door arm section to the
trolley using the 5/16"x1-1/4" clevis pin and ring
fastener.
NOTE: Adjusting the limits on the following page:
• The trolley will automatically connect. If not,
review the trolley lockout feature on page 28.
• When setting the up limit on the following page,
the door should not have a “backward” slant
when fully open as illustrated below. A slight
backward slant will cause unnecessary bucking
and/or jerking operation as the door is being
opened or closed from the fully open position.
23
Nuts
5/16"-18
Lock
Washers
5/16"
Ring
Fastener
Straight
Arm
Bolts
5/16"-18x7/8
Door
Bracket
Clevis Pin
5/16"x1-1/4"
Curved
Door Arm
Door Arm
Closed
Door
Outer Trolley
Emergency Release Handle
Open Door
Door with
Backward Slant
(Incorrect)
Correct Angle
Outer Trolley
Inner Trolley
Inner Trolley