Re: Lubrication of the Mechanism That Drives The Main Sail Furling Unit
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Craig, Kent, et al;
This is the best summary that I can give you of this obviously moving target. Most is based on verified fact, but some is based on logical conclusions. So take this with a grain of salt.
Shortly after Kent posted that, I was in discussions with the original supplier of that gearbox to Amel who is the same guy (no retired) that made the SM genoa gearbox and motor assembly. He said that Kent was correct. The oil that Kent specified is what he recommended. However, the practical usage of this gearbox and the lubrication of the gears causes me to conclude that even though the supplier of the gearbox suggested oil, it is not practical. And, FYI, I believe that every SM that I have seen has a wet input shaft seal. I also believe that as these gearboxes sat new on his shelf, none leaked.
This gearbox and its supplier was changed during the production of the 54. I assume that this change had something to do with no longer buying the genoa gearbox. The guy that originally supplied this gearbox and the genoa furling gearbox and motor retired. The new supplier (unknown to me) of that gearbox possibly "fixed" the poor fit of the oil seal. I know that the new supplier changed one seal in this gearbox from 45mmX60mmX7mm to 45mmX58mmX7mm, because one of my SM clients had one size and a 54 client had the other size.
Also, I should note that some owners observed, "The outer lip seal (for the input shaft) is 30x40x7 but might be a very sloppy fit. Use RTV or machined it out to fit a 30x41x7 Lip Seal." This note is included in my Amel Book for the rebuild of this gearbox.
Although it might have nothing to do with this, there is also an O ring that seals the input shaft plastic cover to the gearbox. Possibly some owners have missed this. One owner measured it as 1.4mm fitting into an O ring groove.
I hope that this helps.
On Fri, Aug 7, 2020 at 8:47 AM Craig & Katherine Briggs via groups.io <email@example.com> wrote:
This may sum it all up - bottom line, grease, not oil: