I am in the process of completely rebuilding the outhaul gearbox on Aletes and am wondering about how well the addition of a grease nipple has worked out for those who have tried it. A couple of engineering concerns come to mind.
1) Should the nipple be low or high in the fitting?
2) The lip seals are very close fitting. Can air escape to the point that grease flows throughout the housing? Especially to the bearing at the end of the worm drive?
3) If a relief hole and plug are put in to allow air to escape, does that easy path preclude grease getting to all the other areas of the housing?
4) If water gets in past the top lip seal, how does applying more grease through fitting push that water out?
5) Would it be better to not install a relief plug and to loosen the screws on the endplates to allow air/water out until the grease gets there?
All these questions make me wonder if it is not better to simply take the gear box apart every couple of years rather than chance under greasing and not getting the water out. Will the grease nipple provide a false sense of security that all is well inside the gearbox when in actuality it is not?
[Water may not be so much of an issue with good lip seals. I think it has been 2 or 3 years since I last had the unit apart to grease and there was no water at all inside. The first time I took it apart after buying the boat used, there was water in the gearbox.]
Bye the way, all the seals and bearings are available in the US from Motion Industries with several hundred outlets around the US. They also offer the service of rebuilding gearboxes although I did not price this out.
s/v Aletes SM#240