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Repowering

Modifying Engine Beds

The engine beds had to be modified. First I picked an engine whose mount points were higher than the original. That gave me more choices of how to modify the beds. I decided on steel rails that are properly spaced side to side but run continuously fore and aft. This allows some adjustment of the engine. Since I can bolt the rails on I don't have to do any welding which would involve removal of combustible material surrounding the pedestals. The engine itself also allows some adjustments at the mounts. The following details the construction of the beds.

Here is the orginal engine bed. The 4 pedestals supported a 550 lb engine. So they would have no problem supporting a new 300 lb engine.

I used this piece of plywood to establish dimensions and locations of the beds and the propeller shaft.

I used two pieces of cedar left over from a fence repair to build prototypes of the steel rails.

I ordered steel bar stock 5/8" x 2 1/2" from Online Metals. www.onlinemetals.com. They cut each piece to 24" long before shipping. When I got them they were very close to the same length. I drilled and tapped 3/8" x 16 holes. Here the steel is shown bolted on from underneath using the existing holes in the pedestals.

I finished these by grinding off the mill scale. Then I washed them with Ospho. After it dried I wiped down with Evaporust. I painted with zinc and finished with white polyurethane. This should be sufficient to keep them from rusting.

When I set the engine in place and get it lined up I will drill and tap holes in the top of the beds to secure the mounts.

I mounted the engine by carefully placing it on the beds. I then performed a prop shaft alignment to the best degree possible. I then marked the beds, removed them, drilled and tapped the holes. Then I put them back in place and bolted the engine down. It was imperative that I completed bolting the engine down before I left the boat. What if there was another "gravity wave" like there had been on Easter night?

There is plenty of room below to inspect for oil drippings and to reach the raw water intake seacock.