When you’re called on to repair a sliding patio door for a customer, you typically won’t have to replace the door, unless the homeowner desires a different look. Depending on what the door needs, it could take an hour or so to clean and lubricate the track, and to adjust and repair or replace the rollers. You can usually find weather stripping, rollers or door latches from home improvement stores, hardware stores or the door distributor. 

Collect Your Supplies

You’ll need the following items: drop cloth; stiff bristle brush; small bucket; warm, soapy water; clean rag; shop vacuum; awl; Phillips and flat-head screwdrivers; silicone spray; paraffin wax block; two sawhorses; small block of wood; and hammer. Have a portable drill handy and a new set of roller assemblies to speed the process of door removal and roller cleaning or replacement. 

Clean and Lubricate the Track

Start with the simple fix by opening the active door and thoroughly cleaning its bottom track. Remove loose dirt and debris from inside the track area with a shop vacuum. Scrub the track with soapy water to eradicate caked-on dirt or mud. Wipe the track dry with a clean rag. 

After cleaning the track, insert an awl through each weep hole in the exterior molding to ensure proper drainage. Avoid chemical cleaners, solvents, abrasives or acid to prevent damage to vinyl sliding doors and rubber rollers. Lubricate the cleaned track with a block of paraffin wax for best results. 

Clean and Adjust or Replace the Rollers

Locate the small plugs in the bottom of the door that cover the screws for adjusting the roller height. If you don’t find them on the bottom sides of the door, check either end of the door -- sometimes the screws are found there. Pop the caps off and use a flat-head screwdriver to adjust roller height. Turn the screw clockwise to create a gap of about 1/8 to 1/4 inch between the bottom of the door and the track for optimum roller height. For best results, adjust roller height when the door is within 1/2 inch of the side jamb. Turn the screw counterclockwise until they completely retract to more easily remove the door if the rollers require cleaning or replacement. 

Remove the Door and Rollers

With the door open, remove the stop molding at the top of the active door with the portable drill. Immediately lift the door out because it could fall into the room and break without the stop molding. Set the door across two sawhorses to expose its bottom. On the bottom of the door, insert a screwdriver into the cavity that holds the rollers and pry them out. Most rollers are held in place by the door’s weight and friction, although some may be held with a screw. 

Examine the rollers carefully for damage. If the wheels have any chips, or if their frames are bent, replace them. Chipped or notched wheels or bent roller frames don’t allow the door to glide smoothly on the rollers and will eventually malfunction anyway. If the rollers are simply dirty, clean them well and lubricate them with a silicone spray that won’t collect dirt or damage the rollers. Insert the roller assemblies back into their cavities with the screw facing the adjustment hole. To avoid damaging the rollers, hold a small wooden block across their length and lightly tap them into the cavity with a hammer. Adjust the rollers so they retract for an easier door reinstall. Replace damaged or worn weatherstripping and door hardware.


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