How to install LiftMaster 8500W Jackshaft Opener

In this guide, we will be going through the steps for installing a LiftMaster model 8500W jackshaft opener on a residential 2-car sectional garage door. We are confident that this guide will help you be a better installer and provide better service and value to your customer.

The LiftMaster 8500W model in this guide includes 841LM powered door lock, integrated model 485LM battery for backup power, cable tension monitor and 827LM remote LED light.

The 8500W can be installed on torsion spring activated door with 1” diameter shaft.

Standard Lift Door Application

  • 15” radius track or greater
  • Up to 18’ wide doors
  • Up to 14’ tall doors

Hi-lift Applications

  • 14’ tall
  • Up to 54” of hi-lift

For installation

  • Minimum 2.5” clearance from the wall to center of torsion shaft
  • Minimum of 3” clearance from ceiling to center of torsion shaft
  • Minimum of 8.5” clearance from side wall to the end of the torsion shaft
  • Torsion shaft must extend 1.5” past the bearing plate
  • Disable any locks installed

“PRO TIP: Before installation, ensure the door is working properly.”

Operator Installation

  • Slide the shaft collar over the motor shaft of the operator and secure it in place. (*The side of the collar with the larger hole should be placed on the motor side.)

“PRO TIP: Place the collar so that the set screws are facing out, making them easier to access.”

  • Next, loosely attach the slotted side of the mounting bracket to the same side of the garage door opener as the motor shaft. (Leave this loose until it is time to secure to the jam.)
  • With the garage door in the closed position, place the opener on the end of the torsion shaft. (Make sure that the shaft collar is clear of the bearing plate and does not make contact.)
  • Next, using a level, position and align the garage door opener. Verify that the mounting bracket is located on a solid surface and secure it using the proper hardware.
  • After connecting the mounting bracket, secure both the coupling and mounting bracket on the operator.
  • Now install the emergency release rope and handle. Mount it within reach and at least 6’ above the garage floor. Ensure that the notice on the handle is right side up and secure it with an overhand knot.

Safety Item Installation

  • Automatic Door Lock Installation -From here we will install the automatic door lock (Part #841LM). The lock must be within 10’ of the opener and the mount must be on the same side.  Placement above the third roller is ideal.
  • Clean the inside of the rail and attach the lock installation template. The hole for the lock bolt should be at least 3 inches from the center of the third roller.  Drill the holes on the template with a 5/16” & ¾” drill bits.
  • Next attach the door lock to the outside of the door trim with the hardware provided.
  • Run the attached bell wire up to the motor head and plug in the connectors.

"The 8500W is capable of having 2 locks installed for added security."

  • Cable Tension Monitor Installation - This required device detects any slack that may occur in the cables and is capable of reversing the door.
  • The first step is to position the cable tension monitor, so the roller is 2” – 6” from the drum & the roller extends past the cable 1/8” – 1/4”. (Make sure the cable is approximately 3/4” from the mounting surface).
  • Next drill 3 3/16” pilot holes & attach the cable tension monitor

“PRO TIP – Make sure the roller is on top of the cable.”

  • Now run the bell wire above and around the opener and connect the wire to the green quick-connect terminal.
  • Infrared Safety Eyes - These must be installed within 6 inches of the bottom of the door
  • Run the bell wire to the opener
  • Install the white wires to the white terminals and the white & black wires to the grey terminal
  • Wall remote Installation – It is recommended you mount the wall remote 5’ from the floor or high enough to be out of reach of small children.
  • Run the red and red & white wires from the remote to the opener.
  • Connect to the red and white terminals on the opener.

Battery Backup Installation

  • Make sure the power is off and connect the red and black wires to the corresponding terminals on the battery.
  • Place the battery in the opener and plug in the opener.   

“PRO TIP: If the opener is in battery backup mode, the MyQ devices will be disabled. The automatic door lock will disengage and remain this way until power is restored.”

Set Garage Door Travel

  • Press the adjustment button until the “up” button begins to flash
  • Press and hold the “up” button until the garage door is in the desired position
  • Press and release the adjustment button. The garage opener lights will flash twice and the “down” button will begin to flash.
  • Press and hold the “down” button until the garage door is in the desired down position
  • Press and release the adjustment button. Programming the garage door travel is now complete.

MyQ Remote LED Light Installation

  • First, pick the desired location and ensure it is within 6’ of an outlet.
  • Drill 6 pilot holes & open the light lens
  • Mount the light with the screws provided
  • Your remote light has already been programed from the factory to operate with your opener. Any additional lights will need to be programmed.

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Safety Disclaimer: In order to see all procedures completely, there may be safety measures that are not taken by our actors. Be sure to follow any and all proper safety requirements and refer to your manufacturer's installation manual for details. Your health and safety is the #1 concern. Failure to understand/follow the recommendations in the course could result in property damage, personal injury or death. While all efforts are made to provide accurate information and guidance, it is impossible to predict all door circumstances. Accordingly, the user agrees that the user of this video; products and information contained herein are at your own risk. In no event shall Service Spring be liable for any property damage, personal injury/death, or any other loss or damage that may result from your use of the information and products provided on this video. All information contained within this site is provided "as-is" without warranty expressed or implied. User assumes all responsibility/risk for use of information and products purchased. If you have any doubts about your ability to perform the work safely, we recommend you contact another door professional to complete your repair.

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