LiftMaster K07-50126 Flex Coupling, Q069
The LiftMaster K07-50126 is a flexible coupling used in the drive train of select commercial gate operator systems. A flex coupling helps connect rotating drive components while absorbing small amounts of vibration and alignment variation between the motor and gearbox or related drive hardware. In the field, this part is usually looked at when the operator motor runs but the connected drive assembly is noisy, loose, slipping, or no longer transferring power smoothly. Because this is a mechanical drive component, correct fitment matters. Similar couplings can have different bore sizes, hub profiles, and mounting styles, so the original part number or operator parts diagram should be used before ordering.
Compatible With
- Select LiftMaster commercial gate operators where the parts diagram calls for K07-50126 or Q069; commonly associated with old-style Hercules / HCT overhead gate operator drive assemblies and other heavy-duty commercial operator layouts that use this flex coupling.
Compatibility should be verified by the operator model number, original part number, and replacement-parts diagram. LiftMaster barrier and commercial gate operator parts often look similar across model families but may use different shafts, collars, hubs, link geometry, or mounting hardware.
Features & Specifications
| Manufacturer | LiftMaster / Chamberlain Group |
|---|
| Product Type | Flex coupling replacement kit |
|---|
| Part Number | K07-50126 |
|---|
| Application | Commercial gate operator drive coupling service |
|---|
| Compatible Operator Type | Select LiftMaster commercial gate and old-style Hercules / HCT overhead gate operator applications |
|---|
| Material / Finish | Heavy-duty mechanical coupling components |
|---|
| Notes | Verify original coupling number, shaft size, hub style, and parts diagram before ordering |
|---|
Also Known As / Related Part Numbers
- K07-50126
- Q069
- 07-50126
- LiftMaster Q069
- Motor to Gearbox Coupling Flex O/H
- Old Style Hercules flex coupling
Technician Note
Before replacing this part, check the surrounding mechanical assembly for looseness, worn pivot points, damaged shafts, missing set screws, bent linkage, or signs of a gate or arm impact. Replacing one worn part without correcting the cause can lead to repeat failure.
Before Ordering Checklist
- Match the manufacturer part number and any older Q/G/07-series number to the original part or parts diagram.
- Confirm the operator model, series, and mechanical assembly location before ordering.
- Inspect adjacent shafts, cranks, bearings, fasteners, and linkage hardware for damage or wear.
- Do not order by appearance only; similar LiftMaster mechanical parts may not interchange.
Important Ordering Warnings
- Do not substitute this coupling by appearance only; couplings can differ by bore, shaft engagement, and drive style.
- If the operator has shaft damage, gearbox play, or broken mounting hardware, those issues should be corrected before replacing the coupling.
Professional Advisory
Mechanical gate and barrier operator repairs should be performed with the operator secured and power disconnected by a qualified gate technician. If the operator has impact damage, binding, unsafe movement, or high-voltage wiring exposure, have the full system inspected before returning it to service.
Product Q&A
What does the K07-50126 flex coupling do?
It connects drive components in select LiftMaster commercial gate operators and helps transfer motor power while allowing a small amount of vibration absorption.
Is Q069 the same part as K07-50126?
Q069 is commonly listed as an alternate or former number for the LiftMaster K07-50126 flex coupling.
Which operators use this coupling?
It is used on select LiftMaster commercial gate operators and is commonly associated with old-style Hercules / HCT overhead gate operator drive assemblies where the parts diagram calls for Q069 or K07-50126.
Can I match this coupling by size only?
No. Shaft size, hub design, set screw location, and operator generation can affect fitment, so the original part number or parts diagram should be checked.
When should this coupling be replaced?
Common reasons include a loose drive connection, damaged coupling, unusual drive-train noise, or power not transferring correctly from the motor side of the operator.
