Introduction
This manual provides detailed instructions for the installation, operation, and maintenance of the Prime-Line U 9861 Sliding Door Keyed Lock. This secondary locking device is designed to enhance the security of your sliding door by preventing prying or lifting. It features a hardened steel bolt for push-button locking and requires a key for unlocking.
Package Contents
Before beginning installation, ensure all components are present:
- 1 x Keyed Lock Assembly
- 2 x Strike Plates
- 2 x Ferrules
- 2 x Keys (Yale Y-13 keyway)
- Installation Screws

Image: Diagram showing the keyed lock, two strike plates, two ferrules, and dimensions (1-3/4" length, 1/2" width, 1" height).
Setup and Installation
This lock is designed for quick and easy installation on the bottom of your patio sliding door. Basic tools such as a drill, drill bits, and a screwdriver are required.
- Determine Mounting Location: Position the lock assembly on the stationary frame of your sliding door, typically at the bottom, ensuring it does not obstruct door operation. The lock should be mounted securely to a solid surface.
- Mark Screw Holes: Hold the lock assembly firmly in place and use a pencil or marker to mark the locations for the mounting screws.
- Drill Pilot Holes: Using an appropriate drill bit size for your screws and door material, drill pilot holes at the marked locations. This prevents wood splitting and ensures a secure fit.
- Mount Lock Body: Secure the main lock assembly to the door frame using the provided installation screws. Ensure it is flush and stable.
- Mark and Drill for Bolt: With the lock body installed, extend the hardened steel bolt. Close the sliding door until it meets the bolt. Mark the exact point on the sliding door where the bolt makes contact. This is where the strike plate will be installed.
- Install Strike Plates: Choose one of the two provided strike plates based on your desired locking position (fully closed or partially open for ventilation). Align the strike plate with the marked bolt location on the sliding door. Mark and drill pilot holes for the strike plate, then secure it with screws. If using the ferrule, drill a larger hole for it to be inserted into the door frame or door edge, providing a reinforced receiver for the bolt.
- Test Operation: With the lock and strike plate installed, test the locking and unlocking mechanism with the provided keys to ensure smooth operation and proper engagement of the bolt.
Important: For optimal security, ensure the lock is installed in a location that provides maximum resistance against forced entry.
Operating Instructions
The Prime-Line U 9861 lock offers straightforward operation:
- To Lock: Simply push the hardened steel bolt inward until it engages with the strike plate on the sliding door. A click indicates it is securely locked.
- To Unlock: Insert one of the provided keys into the lock cylinder and turn it to retract the bolt. The lock uses a Yale Y-13 keyway.
Always ensure the door is fully closed or in the desired partially open position before engaging the lock bolt.
Maintenance
To ensure the longevity and smooth operation of your Prime-Line U 9861 lock, follow these maintenance guidelines:
- Cleaning: Wipe the exterior of the lock with a soft, damp cloth to remove dust and grime. Avoid abrasive cleaners or solvents that could damage the finish.
- Lubrication: Periodically apply a small amount of graphite lubricant or a silicone-based spray lubricant to the keyway and the bolt mechanism. Do not use oil-based lubricants as they can attract dirt.
- Inspection: Regularly check all mounting screws to ensure they are tight. Inspect the bolt and strike plates for any signs of wear or damage.
Troubleshooting
If you encounter issues with your lock, consider the following:
- Bolt does not engage: Check if the strike plate is properly aligned with the bolt. The door might have shifted, or the strike plate may need adjustment. Ensure no debris is obstructing the bolt's path.
- Key is difficult to turn: Apply a small amount of graphite lubricant into the keyway. Ensure you are using the correct key. Avoid forcing the key.
- Lock feels loose: Tighten all mounting screws on both the lock assembly and the strike plates. If the issue persists, inspect the door frame for damage or deterioration.
- Lock is damaged: If the lock body or bolt is physically damaged, it may need replacement. Do not attempt to repair damaged components if they compromise security.
Specifications
| Brand | PRIME-LINE |
| Model Number | U 9861 |
| Lock Type | Key Lock |
| Material | Diecast |
| Finish | Aluminum |
| Item Dimensions (L x W x H) | 1.5 x 3.81 x 5.44 inches |
| Item Weight | 5.6 ounces |
| Included Components | 1 lock, 2 strikes, 2 ferrules, 2 keys, installation screws |
| Keyway | Yale Y-13 |
Warranty Information
Prime-Line warrants goods against manufacturing defects for 1 year from the date of purchase. Prime-Line is not responsible for user-related damage or damage incurred during installation. The warranty is void if products are subjected to abnormal conditions, misapplication, or abuse.
Support
For further assistance, technical support, or to inquire about replacement parts, please visit the official Prime-Line website or contact their customer service department. Refer to the product model number U 9861 when seeking support.







