Mighty Mule MM402 - Manual (Page 17)

rev 082211 Mighty Mule FM402 Installation Instructions 7
IMPORTANT: Determine which side of the driveway you will mount the control box. From this point on, the gate and
gate opener on the same side as the control box will be referred to as the FIRST gate and gate opener. The gate and
gate opener on the opposite side of the driveway from the control box will be referred to as the SECOND gate and gate
opener.
We recommend you position the opener near the centerline of the gate to keep the gate from twisting and flexing
and to avoid backsplash from rain water.
The Post Bracket Assembly
The position of the post bracket assembly
determines the leverage and efficiency of the
opener. The post bracket assembly position
also sets the clearance between the opener
and the gate in the open and closed positions.
The post bracket works well for
installations on round and square fence
posts. Because the post bracket carries the
entire thrust of the active opener, bolts must
completely penetrate the post.
On wood posts, place a metal plate or
washer (not supplied) between the nuts and
the post to prevent the thrust of the opener
from pulling the bolts and washers out of the
wood.
The post pivot bracket may not be necessary on posts larger than 6" in diameter (see page 6). Fence posts smaller
than 6" in diameter or 6" square should be made of metal instead of wood to remain stable while the opener is moving
the gate.
Reinforcing Gates for the Gate Brackets
We recommend using a muffler clamp, wood, or metal, to reinforce thin-walled tube gates, or wood to reinforce panel
gates as shown. These reinforcement methods will prevent damage to the opener and gate. Additional hardware may be
needed depending on the installation.
Muffler Clamp for
Gate Bracket
Wood or Metal
Reinforcement
1" x 6" Wood
Reinforcement
Post
Bracket
Post
Pivot Bracket
Metal Plate Wooden Post
Post
Bracket
Post
Pivot Bracket
Metal Plate Wooden Post
Post Pivot
Bracket
Post
Bracket
Post Bracket
Assembly
Thin Walled
Tube Gate
Gate Bracket
Muffler Clamp
(not supplied)
Gate Bracket
Wood or Metal
Reinforcement
(not supplied)
Gate
Bracket
Panel
Gate
1" x 6"
Wood
Reinforcement
Installation of the FIRST Gate Opener