Raymarine Wheel Pilot

[trapezeartist]

My Autopilot is still driving me mad. I have a Wheelpilot Mk2 which has not been working properly for months. Initially I thought the belt was slipping, but then found that the belt drive pinion on the end of the motor was spinning on the shaft. I have now fitted a new pinion and loctited it on, just to make sure.

At that point I thought everything was sorted and refitted it. Then on testing I found the motor wasn't rotating although it was buzzing and trying to work. On stripping it yet again I found that the pinion would only rotate a couple of degrees either way. It comes to a hard stop in each direction.

There is a gearbox containing an epicyclic geartrain on the end of the motor that provides the reduction from the motor to the belt drive.The photo shows the motor end. Peering down the hole in the middle the three planet gears are visible, and they can be seen to move when the pinion is wiggled to and fro.

Does anyone know how this is constructed? It looks as though the two outer holes are a means of unscrewing the end of the gearbox from the body, and hence getting access to the internals. However I haven't been able to get sufficient purchase on it to make anything move yet, or maybe it doesn't disassemble that way.

If I can manage to get it to pieces I am fairly confident I will find something displaced or a stray bit of something has fallen in and jammed it. In which case I can fix the system without having to pay out a huge amount of beer tokens for a new gearbox.

 

[trapezeartist]

It turned out that the end cap of the gearbox is just pressed in. There is a peg and a flat to "time" so turning it with a pin wrench made it just possible to wiggle it off. As soon as the three planet wheels in the first epicyclic train were removed it rotated perfectly. I cleaned up the planet wheels and found a few of the teeth with slight burrs on them. Once cleaned and re-greased they went back in and all was well.

I can see now what I did wrong. Having removed the electric motor once from the gearbox I refitted it and thought it was back together properly. I now realise that the sun gear on the end of the motor didn't engage into the planet gears so as I screwed the motor down it put the burrs on the plastic gears.

The right way to fit the motor to the gearbox is to first undo the plastic nut at the other end of the motor which hold the wires. The motor can then be slid down so that the sun gear is protruding at then it can be carefully engaged in the planet gears. Then the outer casing is screwed on and finally the nut around the wires is refitted.

After a huge amount of hassle and fiddling I now have the autopilot ready to go back on the boat again. I'm confident it will all work beautifully now (though I said that once before ).

The moral of the story is that it is worth persevering to repair the autopilot. A replacement gearbox would have cost about £180 and I daren't even think what the whole wheelpilot would cost. Once you work out how each bit comes apart it is quite easy. However care needs to exercised at all stages (more care than I exercised originally!).

 

[LadyInBed]

Raymarine Wheel Pilot - Work of the Devil !

 

[wully1]

Raymarine Wheel Pilot - Work of the Devil !

Yup!

The Navico one was better but sadly no longer made.

 

[Mrnotming]

I expect those spare little pinions which strip teeth, which I got from the dealer, were from a cannabalised unit!It was a bit of a scrapyard where these units lay in various states of fettle!

 

[alan17]

It turned out that the end cap of the gearbox is just pressed in. There is a peg and a flat to "time" so turning it with a pin wrench made it just possible to wiggle it off. As soon as the three planet wheels in the first epicyclic train were removed it rotated perfectly. I cleaned up the planet wheels and found a few of the teeth with slight burrs on them. Once cleaned and re-greased they went back in and all was well.

I can see now what I did wrong. Having removed the electric motor once from the gearbox I refitted it and thought it was back together properly. I now realise that the sun gear on the end of the motor didn't engage into the planet gears so as I screwed the motor down it put the burrs on the plastic gears.

The right way to fit the motor to the gearbox is to first undo the plastic nut at the other end of the motor which hold the wires. The motor can then be slid down so that the sun gear is protruding at then it can be carefully engaged in the planet gears. Then the outer casing is screwed on and finally the nut around the wires is refitted.


After a huge amount of hassle and fiddling I now have the autopilot ready to go back on the boat again. I'm confident it will all work beautifully now (though I said that once before ).

The moral of the story is that it is worth persevering to repair the autopilot. A replacement gearbox would have cost about £180 and I daren't even think what the whole wheelpilot would cost. Once you work out how each bit comes apart it is quite easy. However care needs to exercised at all stages (more care than I exercised originally!).

WELL DONE. I hope that your labours are rewarded. Possibly we should all post such valuable pieces of info so we can all learn and save ourselves the cost of a Raymarine repair.

 

[prv]

I daren't even think what the whole wheelpilot would cost.

£200 second-hand, I sold ours a month or two ago

Now much happier with a below-decks ram (£450) - as well as being easier, quieter and more elegant, the pilot also seems to hold course better, possibly due to more direct drive when making small movements.

Glad your wheel drive is sorted for you though.

Pete

 

[sailorman]

Yup!

The Navico one was better but sadly no longer made.

I bust a Navico in 6 months, very badly designed & constructed, got a free replacement @ 14 months & px`d it for a Raytheon 6000, this has never let me down in 14 yrs

 

[trapezeartist]

£200 second-hand, I sold ours a month or two ago

Now much happier with a below-decks ram (£450) - as well as being easier, quieter and more elegant, the pilot also seems to hold course better, possibly due to more direct drive when making small movements.

Glad your wheel drive is sorted for you though.

Pete

I too think the below-deck ram is a much more elegant way of going about things. If cost were no object, I would have put one on. However they are about £900 new, plus whatever bracketry, adaptors and fiddly bits may be required.

I saw your advert for the wheel pilot a while back and had logged it as a possibility in case I ran out of other solutions (though you probably sold it before I was ready anyway). In the end though, my diy repair cost me £24 of actual money, plus the aggravation.