How do I replace the cutless bearing on a Malö 36?

To replace the cutless bearing on your Malö 36, you can either use a mechanical bearing press to draw it out with the shaft in place, or draw the shaft back after disconnecting the engine coupling. Using a puller is far easier because drawing the shaft on this hull shape often requires dropping the rudder to gain clearance.

Sizing and Sourcing

The Malö 36 typically runs a 30mm stainless steel prop shaft. A few boats carry 1 1/4 inch shafts if customised for the US market. Assuming the standard European specification, you need a bearing with a 30mm internal diameter, a 45mm outside diameter and a 120mm length. Vetus (part number CBL30) or Exalto are reliable brands for this application. You can choose a traditional brass-shelled bearing or a phenolic (fibreglass) shell. Brass bearings cost around £45 to £65 and are incredibly durable. Phenolic bearings cost slightly more but eliminate the risk of galvanic corrosion between the bearing shell and the bronze P-bracket.

Removing the Grub Screws

Before attempting to press out the old bearing, you must remove the retaining grub screws. The P-bracket on the Malö 36 usually has two stainless steel M6 or M8 Allen-headed grub screws located on the port and starboard sides of the housing. These are almost always buried under years of hard antifouling paint. Scrape the bracket clean to find them. Dig out the hex sockets with a sharp pick and soak them in penetrating oil overnight. If they refuse to budge, apply localised heat to the bronze bracket using a butane torch. This expands the metal and breaks the corrosion. Wear safety goggles when working under the boat to prevent toxic antifouling flakes entering your eyes. Remove both screws entirely.

Using a Bearing Puller

Pressing the bearing out while leaving the shaft in situ is the preferred boatyard method. You can hire a proprietary tool like a Strut-Pro or fabricate a DIY puller. To make one, you need two lengths of M12 threaded rod, heavy-duty nuts, steel backing plates, a split pusher tube (to fit around the shaft and push the 45mm bearing lip) and a larger receiver pipe positioned aft of the bracket to catch the old bearing.

• Slide your split pusher tube onto the shaft forward of the bracket.
• Position the larger receiver pipe aft of the bracket, sandwiching the setup with your steel backing plates.
• Run the threaded rods through the plates on either side of the shaft.
• Tighten the nuts evenly, working side to side. This forces the pusher tube into the bracket, slowly driving the old bearing out into the receiver pipe.