Re: Main sail Outhaul motor/gearbox failed A54


Thanks Olivier for you very clear explanation.

Possibly the worm and bronze gears inside the gearbox are jammed for two reasons:

The bronze gear is very worn...AND...the helmsperson jammed the outhaul car against the track end-stop. I am fairly sure that you will need a gearbox overhaul or replacement, but you might try removing the end-stop to reduce the jammed pressure on the gears. Be careful not to operate the car too far forward, jamming it against the stop, or beyond the stop. With a worn bronze gear, this jamming will lock the gearbox. I have seen this happen on 54s and even a 2 year old 55. Be especially cautious with new crew as they will almost always misuse/abuse this. 

SM owners may not understand this, but most of this issue is because of a change in gearboxes and motors which is sleeker and better looking, but apparently doesn't take the accidental misuse/abuse that a SM  will take. But, of course, I have also seen accidental misuse kill a SM gearbox. 


CW Bill Rouse
Yacht School - Supporting Amel Owners
720 Winnie St
Galveston Island, TX 77550
+1(832) 380-4970

On Thu, Aug 22, 2019, 3:40 AM Beaute Olivier via Groups.Io <> wrote:
Hello Stefan,

the 100A fuse is a back-up when the power limiting Printed Circuit Board (what you call the Protector) is out of order. In order to connect this fuse, you need to remove both wires from the PCB (just pulling down) and connect them to the 100A fuse.

There seems to be a mechanic problem in the boom gear-box. And therefore, the PCB allows the motor to run for a few seconds, then cuts off power because of too high amperage (that's what it's designed for).
If you connect the back-up fuse, you may blow it within some seconds too because the mechanic resistance is too high, making the amperage rise above 100 A (you may also burn the wires too!!).

It seems that you need to take down the gear-box and open it to check the worm gear and the bronze "teeth wheel".
If you can't find a good skilled mechanic where you are, you may think of just replacing the gear-box (I don't like when you say the shaft went out of the gear-box...).

Good luck and remember to never hit the track end stopper with the traveller. This definitely kills the gear-box after several knocks.


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