Graham Swetman makes his own heavy-duty bearing extractor
My Moody 346 Windwood Notion’s cutless bearing needed replacing – even though it had been replaced only three years earlier. As well as costing more than £300 I was not happy at the way many boatyards do this job – which generally entails the use of a big hammer to drive the bearing out, risking damage to the P-bracket, its mounting and the gearbox.
Then a friend, Victor Jacewicz, explained how he’d made a simple extractor for his boat that would gently press out the bearing, by simply tightening the nuts on two lengths of studding.
All I needed for mine were three small metal plates (about 10cm square and 5mm thick), four nuts, two lengths of studding and a split length of pipe. The pipe had to have a diameter such that, when wrapped around the shaft, it would fit inside the P-bracket, and bear on the bronze casing of the cutless bearing.
The main photo shows how it all works. One plate bears against the prop side of the
P-bracket, and has a hole cut in it large enough to allow the old cutless bearing to just pass through it. The other two plates have a hole diameter the same size as the shaft, together with a cut-out which enables them to be slid over the shaft opposite each other. Then two holes were drilled in each plate to take the lengths of studding. On assembly, the two plates around the engine side of the shaft bear against the split pipe, which in turn bears against the bearing in the P-bracket.
Before using, make sure that any grub screws holding the old bearing have been removed. Then, on tightening the studding, the bearing was forced out through the P-bracket, and through the hole in the lower (prop side) plate – it worked like a dream!
All that remained then was to fit the new bearing. This is normally designed to be an interference fit, and secured in place with two grub screws through the P-bracket. Don’t forget to drill small indentations in the bearing casing to accommodate the points of the grub screws, and use some Loctite on the threads.
Incidentally, a small adaptation of this device gives you a prop-puller as well.
■ Cost: Around £35 – about £20 for the extractor materials and under £15 for the bearing.
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