LiftMaster Q238 / K75-50339 CSW Gate Limit Adjustment Cam

The LiftMaster Q238 is the CSW limit adjustment cam identified by the supplier as manufacturer part K75-50339. LiftMaster also describes this reference as a gate adjustment switch in its parts schedule. It belongs to the documented mechanical limit arrangement on applicable CSW200 equipment and must be matched to the installed assembly. This small service part should not be confused with the separate Q029 electrical limit switch or a complete limit-switch kit. Confirm the original part and operator generation before ordering.

Compatibility — Models, Versions and Exclusions

Separate the Cam from the Electrical Limit Switch

A mechanical limit system uses several components to establish the stopping positions. The cam or adjuster and the electrical switch have different roles, even though they work together in the assembly. Identify the damaged component before ordering. Buying a new cam does not replace worn switch contacts, a damaged holder or a fault in the wiring.

If the gate stops inconsistently or travels beyond its intended position, keep it out of normal service until the cause is diagnosed. A technician should inspect the complete limit mechanism and its mounting, then follow the operator’s adjustment procedure. Do not move a limit setting simply to compensate for a bent arm, binding gate or another mechanical problem.

Specifications and Product Identification

Before Ordering

• Record the operator model and whether the installed assembly is the documented Omni configuration.
• Match Q238 and K75-50339 to the original component or service drawing.
• Inspect the companion switch, holder and adjustment mechanism.
• Confirm whether only the cam or a complete limit kit is required for the repair.

Package Contents and Separate Requirements

This listing identifies the Q238 adjustment component. A Q029 switch, holder, complete limit assembly, control board or wiring harness is not promised as included. Confirm the current carton and any separate fasteners needed. When consulting an exploded drawing, distinguish the individual item number from the larger kit containing several associated components.

Safety Warnings — Read Before Installation or Service

• WARNING: Incorrect travel limits can allow dangerous gate movement. Service requires a qualified gate-systems technician.
• Isolate all applicable power and secure the gate before accessing or replacing limit hardware.
• Do not bypass the limit circuit or operate normally with unreliable stopping positions. Keep people clear during supervised setup.
• After adjustment, verify both travel endpoints and all required reversal and entrapment-protection responses before normal use.

Related Products and Important Differences

• LMRRUL monitored photo eye — a separate protection option only where the exact operator and board approve it; not a universal legacy-system retrofit.
• LMWEKITU monitored wireless edge kit — a separate monitored-edge system requiring documented control compatibility; it does not replace a travel-limit component.

Frequently Asked Questions

Why is this called both a cam and an adjustment switch?

The supplier uses limit cam while LiftMaster’s parts schedule uses gate adjustment switch. The exact K75-50339 reference identifies the offered item.

Is Q029 the same part?

No. Q029 maps to K23-50099, the separate electrical limit switch. Select the component that the diagnosis identifies.

Will it fit every CSW200 operator?

Do not assume that. Confirm the installed limit assembly and the service drawing for the exact generation.

Will changing the cam cure a damaged switch?

No. Inspect both components and their mounting. Replace the parts actually required, then carry out the prescribed setup and safety tests.

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.