Lafree motor noise

[flecc]

Could definitely be something displaced then, either that Hall sensor board or maybe a lost connection within the main unit. You'll need that crank puller, it's a standard thread, and if you split the main unit, circlip pliers for the chainwheel and motor sprocket.
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[Tintaglia]

I have it in (many!) bits now, I have taken some pictures if anyone is interested. The culprit appears to be the hall sensor board as Flecc suspected. The hard plastic pegs that it is mounted on have both snapped off completely leaving it trapped but loose between the case and the motor.

Along the way I discovered that the best way to get the motor off is to take the gear case off the other side first, then it is easy to disconnect the short wires that prevent you from pulling off the motor fully. Unfortunately, this means first removing the motor from the frame but this only involves a few bolts and a couple of wires (apologies if I am repeating what anyone else has already posted).

The other thing to note is that the hall sensor board wiring should be disconnected from the main circuitboard inside the gearcase and pulled through, NOT the plug directly on the back of the hall sensor circuit board itself, which is not detachable.

My problem now is how to re-attach the hall sensor circuit board to the motor (you can see where it has broken away on the first picture). I was thinking of a couple of dobs of glue but I am not sure if the glue would react badly with the circuit board. Does anybody know anymore about this?

Here are some of the pictures:

[flecc]

Yes it's best to remove the crankcase half first, but I thought you'd seen the pictures on my site here Tintaglia? Apologies for not drawing your attention to them if that's not the case, since I've already shown the internals.

I've found it's easiest to locate the board with a screwdriver blade during replacement of the motor, and with a touch of grease or vaseline holding the retaining rubber washers on the screwdriver blade, pushing them into place with that before finally closing the motor/crankcase interface.

Those rubber washers that push onto the post ends are easily missed during stripping and that's why I mentioned them earlier. As the posts have snapped off, you can glue the board using most adhesives, but make sure the position is exactly right in relation to the snapped off posts for the motor to time correctly.
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[Tintaglia]

Thanks for that Flecc. Sorry about the repetition. I had looked at your pictures, but because my posts had broken it all looked a bit different somehow. Also, I was keen to show that the Hall sensor comes with it's loom attached in case someone in the future breaks something trying to yank the wires directly off the back of the board.

Your website description is excellent but I've never been very good at following written instructions, I just have to get my hands on things before I really understand them

So I don't make a horrible mistake, can you just confirm that the rubber washers fit (as it appears from your description and seems logical) between the Hall sensor board and the aluminium case and not between the hall sensor and the motor?

Do you think I could use superglue to hold the washers in place in the absence of the posts?

[flecc]

That's right, the rubber washers push onto the posts after the board is attached, so they sit between the printed circuit surface of the board and the alloy casing.

If you thoroughly clean the black plastic motor wall surface and the slot area of the board, gluing should be ok. but I'm not so sure with superglue. Some types are thicker and will fill a very small gap, but most need an intimate contact between two surfaces which the components like the three Hall sensors will prevent.

I think the best way is to find something just over the thickness of the Hall sensor chips, cut two suitable pieces and glue them centrally over the broken post points. Then you can glue the board to those. Maybe a scrap of rubber or plastic or even wood will do for that. The important thing is that the lateral positioning of the board is accurate, ending up exactly where it would be if it were on the posts, and just about touching the motor wall.
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[Tintaglia]

I'm experimenting with epoxy putty (didn't seem very good) and araldite at the moment to fix the hall sensor board to the motor. I was even wondering about investing in a hot glue gun because I'd like to make sure whatever I use will last under the conditions. On my motor there appears to be a slight recess to allow for the thickness of the hall sensors so I should be able to get a good adhesion between the lugs and the motor.

I was only thinking of using superglue just to fix the rubber washers back in place. I don't think they are strictly necessary once the board is glued in but I thought they might help to protect it from vibrations etc.

[flecc]

Those rubber washers could be useful for that.

The hot glue gun might well work on that motor wall. That type of black plastic encasing the motor is quite difficult to stick anything to, but be careful none of the hot glue hits the sensors.
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[electric.mike]

i don't know the actual situation you are working in but i use a hot glue gun for wood work, if you need to spot glue it in more than one place you may not have enough working time with the glue, would a two part filler adhesive be better like plastic padding or silicone
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mike

[Tintaglia]

I need your help yet again flecc! Just as I thought I was on the home straight, I have discovered that the small bearing on the motor shaft is all but siezed. It will only move about an eighth of a turn before it locks. Can you have a look at yours and see what it feels like? I hope it hasn't been turning in the ally case...

I can hardly believe it wasn't noisier but I'm fairly sure it really is worn out.

[flecc]

Can you tell me exactly which bearing you mean so that there's no confusion?

If it's showing in my site, you can tell me which one from that.