Your boat will now be between twenty and thirty years of age and, if it has been permanently moored for any length of time your swing keel is well overdue for a thorough inspection.
Although originally designed to withstand five times the strain normally required to lift the keel, the point where the lifting rod or cable is connected to the reduced thickness section on the keel may have been weakened by electrolysis, and although the cast iron keel is the closest metal possible on the galvanic scale to the 316 stainless connecting pin and fitting, and because it was not possible to make both components of the same metal a very weak electric current would be present when immersed, this would have the effect of slowly depositing metal from the keel around the hole on to the pin and fork fitting. If the keel at this point is lifted clear of the water very little damage will occur, but, for boats where the keel has been left in the lowered position weakening will have occurred, space was left in manufacture to drill a new hole in unaffected metal on the keel if necessary.
Note that in the warmer northern waters reaction will be more severe than in colder southern states.
It is also important to note that the pivot bolt is just that, it is not meant to be a close fitting bearing. The keel was drilled oversize to take pivot bolt and to allow the heavily reinforced area around the keel case take all of the strains involved, the keel should not be bushed to make a neat fit on the bolt
Should your keel be showing signs of severe pitting it should be water blasted to remove the old antifouling, filled with epoxy based filler and recoated with epoxy or a tar epoxy paint.
It is recommended that you lower and raise the keel at least once a month if your boat is moored and not in regular use, also a strap to take the weight off the hydraulic ram when not in use will extend the life of the hydraulics.
Some notes to assist in the removal and replacement of a RL28 keel.
Removing and replacing a keel can be quite difficult and potentially dangerous task, and it is well worth the trouble to construct the device shown here. It will save you considerable time and worry. It can be made from scrap material found in any steel fabricators scrap bin.
Besides the device, you will need just two short lengths of timber of the same thickness as the 600mm long rod in the device.
To remove the keel.
Lower the boat as shown in sketch 2, with a short length of timber placed 50mm clear of the keel slot at each end. The device should be placed about 100mm forward of the centre of the slot with the handle and uprights in the flat position.
Lower the keel until it is sitting on the device, disconnect the lower part of the ram lifting rod and remove the keel bolt (if you are lucky the bolt will partially screw out by turning the head anticlockwise) Lift the boat half way up off the keel, and lift the handle of the device to the upright position, and lift the boat clear.
The keel will now be safe in the upright position as shown in sketch 3.
To replace the keel in the boat.
First tape the ram lifting rod to the horn at the top of the keel. Lower the boat over the keel, and when halfway down lower the device handle to horizontal and let the boat all the way down. The keel will now be close to balanced sitting on the raised nob on the bar and the pivot hole can be easily moved up or down 30mm inside the case.
A tapered piece of dowel can be used align the pivot hole in the case with the hole in the keel.