Re: Main sail Outhaul motor/gearbox failed A54

Craig Briggs

HI Stefan,
Wow! This sounds like a good mystery!
I have inserted my thoughts in your post below in Red Type.

On Wed, Aug 21, 2019 at 03:55 PM, Stefan Schaufert wrote:
Dear AMEL Group/ Owners,

our main sail outhaul (gearbox) stopped 2 days ago just in the moment the main was completely furled in.
First we thought it is a kind of end-switch that stoped it and does not release.  No, there is no end-switch (like the one on your bow thruster - good guess, but not the cause)
But it never worked again. (It will!  It will ! :-)
Today I checked the entire system:
- by switching there is a clicking, thus the relays + switches are working Yes, that should be true. However, the low current electromagnet in the relay (contactor) could be OK and give you a "click" but the high voltage contacts could be bad and no current would go to the motor.  I think that is unlikely, so let's keep going.
- I changed/swapped the cables from the mast furler with the boom outhaul (on the breakers, the current protectors and the relays): mast furler is working, boom not. So the problem must be in the boom, not the mast, is what I think this means.  
- I checked the gear box: the shaft (I guess with the worm drive - I can not open the box.) was about 1cm out of the gear box (the cover was kicked out - see picture with marking) + fully blocked. OMG!! that's horrible - sounds like a REALLY bad gear box!  But let's keep going.
Was/Is the gear box broken or is it a safety thing? Gear box - there is no safety thing, definitely.
I pushed the shaft slowly (with a small hammer and a protector) back + put the cover on, then the shaft was turning again well and easy. Cool!
- I checked the motor: brushes are still very well (very good :-), power comes, the motor turns (when not connected with the gear box AND when the cables on the current-protectors (What is the right name?) (I think you mean the "relays" or also called "contactors" ) - see picture - are swapped). The motor turns not, when the current protectors are default connected (boom to boom, mast to mast). This is the boom motor, not the mast motor (which is OK) - correct?
- OK. I connected the motor (the boom outhaul motor, right?) again with the gearbox (current protectors still swapped). Motor turns short and stops, then trying to turn but does not make it. This really sounds like it's the gear-box (reductore in Italian, or reducing gear). 
- Swapped the cables for the current-protectors back (boom to boom, mast to mast). Mast is working, boom not (only the relay is clicking). Is it "trying" to turn, but stopping immediately? That is what it seems to me from reading your post.
But why is the mast furler working with the boom-current-protector and not the boom itself? It seems that is because the mast motor and gear are OK but the boom gearbox is preventing the boom motor from turning? The boom motor is trying to turn with electricity from either the boom relay or the mast relay. It can't turn when it is connected to the boom reduction gear because that gear is bad.  That is what it seems to me at this point - I may be wrong.
And, btw: there are 2 spare breakers 100A, but no slot for it??? I don't know about that - maybe they are just spares.

Now I do not know:
Is it only the current-protector I would guess that is not the problem
the gear box too That seems like the problem to me.
the motor (which is looking very well)Because both motors run fine without their gearboxes attached, they both seem OK.  Unless I did not understand something.
Or all of it? 
I am looking forward for your help and really appreciate it.
Best regards
A54 N°119 Lady Charlyette, currently Leixoes/Porto

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