How to Remove a Volvo SX Stern Driveby Will Charpentier Updated October 25, 2017
Items you will need
Two 4 inch-by-4 inch pieces of lumber, 25 inches long
Banding tool and banding material
5/8-inch swivel socket
5/8-inch wooden dowel, 20 inches long
Stern drive O-ring kit
If your inboard-outboard boat is equipped with a Volvo stern drive, you quickly learn that Volvo has a habit of doing things logically. If you have basic mechanical knowledge and skills, you'll find that removing the Volvo Penta SX stern drive is a straightforward process. When you remove the stern drive, the process can take an hour or less the first time you do it. During reinstallation, things get a bit more complicated. You have to slather grease on some things, daub gasket sealant on others, and align and reconnect the shift shaft and drive shaft.
Remove the bellows from the stern drive, using a 5/8-inch wrench. Attach two 4x4s to the lift of a motorcycle jack using a banding tool. Slide the jack under the stern drive and raise the jack to support the stern drive.
Remove the six nuts in the three insets on each side of the stern drive, using a 3/8-inch-drive ratchet and a 5/8-inch swivel socket. Use a cir-clip tool to remove the clips from the ends of the pin that goes through the stern drive to hold the pistons of the trim-tilt cylinders to the stern drive.
Place the end of a 5/8-inch wooden dowel against the starboard end of the pin that goes through the stern drive and the ends of the trim-tilt pistons. Drive the dowel through the stern drive to knock the pin out of the cylinders and the stern drive. Place the pin in a safe place.
Turn the shift rod counterclockwise until it comes free. Count the number of turns you must make to free the shaft, so you don't have to readjust it when you replace the stern drive. Pull the stern drive away from the driveshaft and boat.
Reverse the process to install the stern drive. Spread a thin layer of gasket compound on both sides of the two, new O-rings in for the exhaust and driveshaft. Replace the O-rings.
Push the stern drive into place and reconnect the shift shaft by screwing the shaft back into the sleeve the same number of turns used to loosen it. Lubricate the lip of the pinion bearing carrier -- the upper opening on the face of the stern drive -- with marine grease.
Slide the Volvo driveshaft alignment tool through the gimbaled bearing and into the engine coupler to ensure alignment. Apply a dab of gasket sealing compound to the threads of the six mounting studs. Apply a coat of molybdenum grease to the spines on the driveshaft.
Move the stern drive forward so the driveshaft and universal coupler slide easily into the U-joint bellows on the stern drive. If necessary, turn the driveshaft until the splines fit into the flywheel coupler in the stern drive.
Push the stern drive all the way onto the studs and thread the nuts on by hand. Tighten the nuts to 28 foot-pounds with a torque wrench, then tighten the nuts to 50 foot-pounds in a crisscross pattern, starting with the center nuts. Install the bellows, applying gasket sealer to its sealing surfaces to form a watertight joint.
Align the starboard trim-tilt piston with the bore on the starboard side of the stern drive. Insert the pin through the piston and bore until you see the pin at the port side of the drive. Align the port trim-tilt piston with the pin and push the pin through the piston. Apply a bit of gasket sealer to the groove on each end of the pin and reattach cir-clips to the ends of the pin.
Always use new clips, gaskets and O-rings on this project. They're far less costly than the results of not doing so.
Volvo recommends Volvo lubricants and sealants, but any good, waterproof marine grease is suitable. Any molybdenum grease is suitable for use on the Penta SX driveshaft.
Disconnect the negative cable of the boat’s battery before performing any maintenance work on the boat’s engine or stern drive, using a 5/16-inch box end wrench. Lift the cable from the battery, move it outside of the battery box and close the lid of the battery box. After the work is complete, reconnect the negative battery cable.
Will Charpentier is a writer who specializes in boating and maritime subjects. A retired ship captain, Charpentier holds a doctorate in applied ocean science and engineering. He is also a certified marine technician and the author of a popular text on writing local history.