Chamberlain 311 Connect Door Arm to Trolley, Figure, Figure, Figure, Figure 1:, Figure 2:, SECTIONAL DOORS ONLY, Figure 3, Hole alignment alternative:

INSTALLATION STEP 12

Connect Door Arm to Trolley

Follow instructions which apply to your door type as illustrated below and on the following page.

Inner Trolley

Outer Trolley

SECTIONAL DOORS ONLY

•	Make sure garage door is fully closed. Pull the
	emergency release handle to disconnect the outer
	trolley from the inner trolley. Slide the outer trolley
	back (away from the door) about 2" (5 cm) as
	shown in Figures 1, 2 and 3.
•	Figure 1:

Ring Fastener

Door

Clevis Pin 5/16"x1"

	– Fasten straight door arm section to outer trolley
	with the 5/16"x1" clevis pin. Secure the
	connection with a ring fastener.
	– Fasten curved section to the door bracket in the
	same way, using the 5/16"x1-1/4" clevis pin.
•	Figure 2:
	– Bring arm sections together. Find two pairs of
	holes that line up and join sections. Select holes
	as far apart as possible to increase door arm
	rigidity.
•	Figure 3, Hole alignment alternative:
	– If holes in curved arm are above holes in straight
	arm, disconnect straight arm. Cut about
	6" (15 cm) from the solid end. Reconnect
	to trolley with cut end down as shown.
	– Bring arm sections together.
	– Find two pairs of holes that line up and join with
	bolts, lock washers and nuts.
• Proceed to Adjustment Step 1, page 28. Trolley will
	re-engage automatically when opener is operated.

HARDWARE SHOWN ACTUAL SIZE

Nut 5/16"-18 Lock Washer 5/16" Ring Fastener

Clevis Pin	Clevis Pin	Hex Bolt
5/16"x1" (Trolley)	5/16"x1-1/4" (Door Bracket)	5/16"-18x7/8"

BracketStraight

Door Arm

Curved

Door Arm

Clevis Pin 5/16"x1-1/4"

Figure 1

Lock

Washers 5/16"

Nuts
5/16"-18	Emergency
	Release
	Handle

Bolts 5/16"-18x7/8"

Door Bracket

Figure 2

Lock

Washers 5/16"

Nuts 5/16"-18

Bolts 5/16"-18x7/8"

Cut This End

Figure 3

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