2a.
The chain or belt needs to be tightened inside
the rail.
2b.
Make sure carriage and bullet are not engaged. To
disengage the carriage, pull the red cord and move
carriage away from the bullet.
2c.
Prior to tightening, check to make certain the
tension bracket is hooked into the rail as shown
in Illustration 2c. Manually tighten tension nut
with wrench until chain/belt is approximately 1/8"
above bottom edge of rail,
measured at midpoint of rail.
3a.
Flip the rail (A) over with the open side
facing down.
Lower the drive gear over
the spline shaft on top of the powerhead so
that the powerhead's light lens is facing
away from the door.
3b.
Place rail mounting bracket(s) (G) over rail
and align with holes in powerhead.
3c.
On Belt drive models,
align the tongue of
the Belt Guide bracket (I) with
slot and align holes in powerhead.
On Chain drive models,
utilize
a second mounting bracket (G)
and align with holes in
powerhead.
3d.
Fully tighten 1/4"-14 - 5/8"
screws. Do not over tighten.
NOTE:
To prevent damage to motion sensor,
DO NOT
remove foam cushion from
underside of powerhead.
Protective
foam cushion
Slot
Slot
I
3c
Exposed thread at
tension nut (approx.):
• Belt = 3/8" to 1/2"
• Chain = 1/2" to 5/8"
Bullet
B
2b
B
Carriage
2c
3/8" to 5/8"
exposed
Bottom
of rail
Using tension adjustment
maintain 1/8" gap between
chain or belt and inside
bottom of rail at midpoint
of rail.
CHAIN/BELT
A
Light
lens
1/4"-14 x 5/8"
Tapered flange
screw (x4)
G
I
3b
DOOR
3a
AdJustInG rAIl tensIon
AttACh rAIl to poWerheAd
(BLUE BAG)
4a.
Determine “highest point of door travel”:
1. Get on a ladder to the side of your garage door.
2. Have someone lift the door open slowly.
3. As the door is raised, find the highest point where the door extends above the door tracks—that is
the highest point of door travel. For sectional doors this is typically where the top door roller exits the
curved portion of the track onto the horizontal section as the door is raised.
4. With a tape measure, determine the distance from the highest point of door travel to the floor.
4b.
Place a mark on the header at the highest point of door travel, preferably at the center of the door
(measured side to side).
4c.
Position the header bracket above the highest point of travel:
· 2-1/2" above for sectional (hinged) doors.
· 6" above for one-piece (non-hinged) doors.
4d.
Drill 5/32" pilot holes in header and secure bracket with 5/16" x 1-3/4" lag screws.
Highest Point of Door Travel
Typical Installation
WA R N I N G
Door springs are under high tension. If spring or shaft is in the way, measure above spring or shaft on the
garage door centerline and mark as location for header bracket.
DO NOT ATTEMPT TO MOVE, ADJUST,
Or rEMOVE DOOr SPrING!
C AU T I O N
Header Bracket must be fastened to garage framing.
DO NOT
fasten to drywall, particle board, plaster, or
other such materials.
4a
Highest point
of travel
Track
Header
bracket
Header
Sectional
door
2-1/2" above
Highest point of door travel
Distance from the
highest point of
door travel to the floor
4b-d
5/16" x 1-3/4" Lag screw
Header
Door centerline
Door centerline
Header bracket
Highest point
of door travel as
door opens
Plus 2-1/2" for
sectional doors
Plus 6" for
one-piece doors
mountInG rAIl brACKet
on heAder
(OrANGE BAG)
