Fasten The T-Rail To The Motor Unit - Chamberlain 3112EM FS2 Owner's Manual

ASSEMBLY STEP 4

Fasten the T-Rail to the Motor Unit

• Place the opener on packing material to protect the
cover. For convenience, put a support under the cable
pulley bracket.
• Remove the two 5/16"-18x1/2" washered bolts mounted
in the top of the motor unit.
• Align the holes in the back section of the T-rail with the
holes in the motor unit.
• Fasten the rail with the two washered bolts previously
removed. Tighten securely. Remember to use only
these bolts! Any other bolts will cause serious
damage to the opener.
• Insert a 5/16"-18x7/8" hex bolt into the cover protection
bolt hole in the T-rail as shown. Tighten securely with a
5/16" lock washer and nut.
NOTE: This bolt prevents trolley over-travel. Keep a 38
mm minimum between the trolley and this bolt when
adjusting travel limits (see page 29).
MODEL 3122EM ONLY:
• Attach chain spreader with #8x1" hex screws and
washers as shown.
HARDWARE SHOWN ACTUAL SIZE
Hex Bolt
5/16"-18x7/8"
Nut Lock Washer
5/16"
5/16"-18
To avoid serious damage to opener, ONLY use bolts/fasteners
mounted in top of motor unit.
Washered Bolt
5/16"-18x1/2"
Hex Bolt
5/16"-18x7/8"
Cover
Protection
Bolt Hole
Rail
(Back
Section)
Lock Washer
5/16"
Nut
5/16"-18
12
USE ONLY THIS
TYPE AND SIZE
BOLT