Slide-Out Motor Replacement for NEWMAR BAY STAR
This comprehensive guide will walk you through repairing slide-out motor replacement on your NEWMAR BAY STAR. Follow each step carefully and gather all required parts before beginning.
Required Parts
- Lippert slide-out motor assembly – Part Number: LC368446 or equivalent, Price Range: $200-$350
- Slide-out lubricant
- Wire connectors
Step-by-Step Instructions
Step 1: Slide-Out System Diagnosis and Type Identification
Thor Four Winds models utilize different slide-out systems depending on model year and floor plan, with the most common being Lippert’s electric rack-and-pinion system or the Schwintek in-wall system. Accurate system identification is critical before ordering parts or attempting repairs. Start by determining whether your slide-out issue is electrical, mechanical, or both. Position your RV on level ground and ensure your battery voltage is at least 12.5 volts – low voltage is a common cause of slide-out problems that appears as mechanical failure. Attempt to operate the slide-out from the control switch, listening carefully for any sounds. A humming noise with no movement suggests a mechanical jam or stripped gear. A clicking sound indicates a relay is engaging but the motor isn’t receiving power. Complete silence suggests an electrical problem upstream of the motor. If only one side of a slide-out moves (common with dual-motor systems), you’ve likely identified a specific motor failure.
Step 2: Accessing Slide-Out Components
The method for accessing slide-out components in the Thor Four Winds varies significantly depending on whether you have a through-frame system (older models) or an in-wall system (newer models). For through-frame systems, the motor and mechanism are accessible from beneath the RV, requiring you to crawl under the coach. Use wheel chocks and jack stands for safety even though you won’t be lifting the RV. For in-wall Schwintek systems (most common in 2016+ models), access is from inside the RV by removing decorative trim along the slide-out perimeter. These trim pieces are secured with square-drive #2 screws (not Phillips) placed at regular intervals. Carefully remove these screws and gently pry the trim pieces away from the wall, being mindful not to crack the plastic. Behind the trim, you’ll see the slide-out mechanism rails, gears, and motor. Take extensive photographs before disturbing anything – slide-out mechanisms have specific positioning requirements.
Step 3: Electrical Testing and Motor Diagnosis
Before removing any components, perform electrical testing to confirm the motor itself has failed rather than a wiring or switch problem. Using a digital multimeter set to DC voltage, test for 12V power at the motor connector when the slide-out switch is activated. If you have 12V at the motor but no operation, the motor has failed. If there’s no voltage at the motor, trace the wiring back toward the control switch, checking for loose connections, corroded terminals, or blown fuses. The Thor Four Winds slide-out system includes inline fuses (typically 30-40 amp) located either in the main distribution panel or in an inline fuse holder near the motor. Test these fuses with the multimeter’s continuity setting. For dual-motor systems (common on larger slide-outs), each motor operates independently but shares a common control switch and power source. If one motor works and the other doesn’t, you’ve isolated the problem to that specific motor.
Step 4: Motor Removal and Replacement
With the faulty motor identified and power disconnected (remove the slide-out fuse), you can proceed with motor removal. For Schwintek systems, the motor is attached to the gear mechanism with a single set screw visible on the motor coupling. Use a hex key (typically 3/16″ or 5mm) to loosen this set screw, turning counterclockwise. You may need to apply penetrating oil if the screw is corroded. Once loosened, the motor should lift straight up and out of the gear mechanism. The electrical connector is usually a multi-pin plug that disconnects by squeezing release tabs and pulling. For rack-and-pinion systems, the motor bolts to a mounting bracket with two or three bolts. Remove these bolts and disconnect the wiring harness. Inspect the drive gear or coupling on the old motor for wear – if the teeth are rounded, chipped, or show significant wear, the entire gear mechanism may need replacement along with the motor.
Step 5: Gear Mechanism Inspection and Lubrication
With the motor removed, you have an excellent opportunity to inspect and service the entire slide-out gear mechanism, which is often the root cause of motor failure due to excessive friction and binding. Using a flashlight, examine all visible gears, racks, and rails for debris accumulation, rust, or damaged teeth. Wipe all components clean with lint-free cloths, removing old, hardened grease and any debris. Check the gear alignment carefully – misaligned gears cause excessive motor load and premature failure. Inspect the slide-out rails or tracks for proper alignment and any signs of bending or damage. Once cleaned, apply fresh lithium-based slide-out lubricant to all moving parts. For Schwintek systems, use a dry lube spray (not wet grease) on the gear teeth and rails to prevent dust accumulation. For rack-and-pinion systems, apply white lithium grease to the rack teeth and rollers. Manually move the slide-out slightly (just an inch or two) to ensure smooth operation before proceeding.
Step 6: New Motor Installation and Alignment
Install the new motor in reverse order of removal, paying careful attention to proper alignment with the gear mechanism. For Schwintek systems, position the motor shaft coupling over the gear mechanism drive shaft, ensuring any locating pins or flats align correctly. Lower the motor into place and thread the set screw through the coupling into the drive shaft, but only finger-tighten initially. Connect the electrical harness firmly until it clicks. For rack-and-pinion systems, bolt the motor to its mounting bracket with all fasteners, again finger-tight initially. Before final tightening, perform a test cycle by temporarily reconnecting power and momentarily activating the slide-out switch for just 1-2 seconds to verify the motor engages the mechanism correctly. Listen for any grinding or unusual noises. If operation is smooth, turn off power and fully tighten all fasteners and set screws to manufacturer torque specifications (typically 8-10 ft-lbs for motor mounting bolts).
Step 7: System Testing and Seal Maintenance
With the new motor installed, perform a complete system test by fully extending and retracting the slide-out at least three times, observing for smooth, even movement without binding or unusual noise. Pay attention to the speed and smoothness of operation – the slide should move at a consistent speed without jerking or hesitation. If your Four Winds has a dual-motor slide, both sides should move in perfect synchronization. If you notice one side moving faster or slower, the motors may need synchronization (a process that varies by system but usually involves removing power mid-cycle to reset timing). While the slide is extended, inspect all rubber wiper seals around the slide perimeter for damage, cracking, or compression set. Apply rubber seal conditioner to these seals to maintain flexibility. Reinstall all interior trim pieces in reverse order, ensuring each piece seats properly before tightening screws. Don’t overtighten trim screws as this can crack plastic. Schedule regular slide-out maintenance every six months including cleaning, lubrication, and seal inspection to prevent future motor failures.