LiftMaster Q090 HCT Plastic Plug — Reference K80-20078

The LiftMaster Q090 identifies the plastic-plug service component shown in the documented HCT overhead-gate operator parts arrangement. Later manufacturer service information associates it with K80-20078. Match the actual plug location, opening and current service recommendation before ordering; this is an individual mechanical component, separate from the trolley body, dolly cover and complete overhead-gate drive. Select the replacement by the complete part number and the installed equipment configuration. A similar photograph or a shared LiftMaster brand name does not establish interchangeability. Confirm the applicable service drawing before ordering so the repair addresses the correct component and its related mounting, connection and operating requirements.

Compatibility — Models, Versions and Exclusions

Identify the Assembly and Plan the Repair

Identify the plug’s actual position in the installed assembly before selecting a replacement. A missing plug may be associated with damage to the surrounding opening or another attachment component. Compare the service callout and the old part, if available, and confirm any unstated fit dimensions rather than choose a generic plastic cap from a similar photograph.

The manufacturer’s plastic-plug description does not establish a load-bearing role, watertight seal or electrical enclosure rating. Confirm the current supplied plug and its intended retention arrangement. Have qualified personnel secure the overhead gate and follow the correct access procedure before service, then verify that the fitted plug and surrounding parts remain clear of the moving mechanism. Replace separately damaged trolley or cover pieces as required.

Compare the replacement with the installed service arrangement before dismantling the equipment. Photograph the part’s location and record the complete model and visible service numbers. Inspect the surrounding attachment points and mating components for wear, impact damage or misalignment. Replacing one worn item will not correct a damaged support or another component that continues to impose abnormal loads on the repaired assembly.

Specifications and Product Identification

Before Ordering

• Record the complete HCT model and service revision.
• Match Q090 / K80-20078 at the correct location.
• Inspect the receiving opening and retention features.
• Confirm current plug quantity and complete fit details.

Package Contents and Separate Requirements

This offer identifies the plastic-plug service item. Confirm current quantity. A trolley body, dolly cover, shaft, release mechanism, mounting bracket and complete overhead-gate operator are not established as included. Do not infer a full trolley package or additional sealing hardware from an assembled-equipment illustration.

Safety Warnings — Read Before Installation or Service

• WARNING: A moving gate and exposed hct plastic plug — reference k80-20078 can cause serious injury. Installation and service require a qualified gate-systems technician.
• Isolate AC power, batteries and any solar supply as applicable, and secure the gate against unexpected movement before work begins.
• Keep people clear of the gate and drive during supervised testing. Never bypass required entrapment-protection devices or increase force to overcome a mechanical fault.
• Restore all covers and guards, then verify travel endpoints, reversal and every required safety device before returning the gate to normal operation.

Related Products and Important Differences

• LMRRUL monitored photo eye — a separate protection option only where the exact operator and control revision approve it; not a universal legacy retrofit.
• LMWEKITU monitored wireless edge kit — a separate edge communication system for approved controls and resistive edges; not a replacement for this mechanical or electrical service part.

Frequently Asked Questions

Is K80-20078 a related reference?

Yes. The manufacturer service list associates K80-20078 with plastic plug Q090.

Is this the complete trolley body?

No. The trolley body and cover have separate service identities.

Does it create a weatherproof seal?

No sealing or environmental rating is established here. Use the approved plug at its intended location.

Will any similarly sized plastic plug work?

No universal substitute is established. Match the actual opening, retention geometry and current service recommendation.

Need Help Confirming the Right Product?

Contact Garage-DoorParts.com before ordering. Send the full equipment model, readable part labels and photographs of the installed assembly. Include the dimensions, electrical configuration or accessory details relevant to your project so the listing can be checked against the actual installation.