Remote control boats have electrically operated servos that allow them to maneuver, pick up speed and stop. Just like full-sized boats, RC boats can take on water through the drive shaft. The typical RC drive shaft uses a universal joint driven off the engine to propel a shaft through a stuffing box. The shaft exits the hull and connects to a propeller. Sealing the drive shaft against leaks requires a few tools and products to perform the procedure correctly.
Set the RC boat on a workbench, cushioned underneath by some foam or rags. Examine the location of the drive shaft where it exits the bottom of the boat. Look for cracks in the wood or fiberglass, depending upon the construction type. Use a screwdriver to loosen and remove the front drive shaft universal joint set screw. Use the screwdriver to remove the rear universal joint set set screw in front of the strut location. Refer to their location in your owner's manual.
Use a screwdriver to remove both front and rear coupler set screws on the drive shaft. Pull the drive shaft out of the stuffing box. Clean the drive shaft with steel wool and carburetor cleaner. Wipe it dry with a rag. Use pliers to twist the stuffing box tube from side to side if it appears loose. Pull it out, but remember its depth position in the hull.
Clean the inside of the stuffing box with carburetor solvent and a pipe cleaner. Wipe the outside of the stuffing box tube with acetone and dry buff with a rag.
Clean the inside of the stuffing box tube guide hole that goes through the hull, with acetone and a pipe cleaner. Use a pipe cleaner to coat the inside of the guide hole with marine epoxy adhesive. Apply epoxy adhesive on the stuffing box tube and reinsert back into the hull hole, in the exact position it came out.
Wait for the adhesive to dry. Insert marine stuffing box grease into both ends of the stuffing box, pushing it into the tube ends with a pipe cleaner. Apply stuffing box grease on the drive shaft and insert it back into the stuffing box tube.
Connect the front drive shaft coupler set screw with a screwdriver. Connect the front universal joint to the front coupler and tighten the set screw.
Connect the rear coupler to the drive shaft and tighten the set screw with a screwdriver. Connect the rear universal joint to the rear coupler and tighten the set screw. Use some 400-grit sandpaper to sand the area around the stuffing box tube on the inside of the boat and the outside. Wipe clean with a rag.
Apply a bead of waterproof silicone around the stuffing box joints on the inside and outside of the hull. Wait for it to dry at least 24 hours and test the boat in the water.
