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#288034 14/07/15 03:04 PM
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My M3W 2012 starting problem was nothing to do with the heated seats, but rather a rectifier on its way out! I've now replaced it, but I'm now looking at how I can prevent the new one (£300 - ouch!) going the way of the first. Or was it the second as the one I removed had two earth wires.

I believe the latest M3Ws have the rectifier mounted along the length of the car, i.e. twisted through 90 degrees, but still mounted at the f/o/s (rhd M3W). Is this so?

Has anyone any other suggestions to make regarding protection for this exposed and expensive item?


Benfro Mog
AMC #288038 14/07/15 03:17 PM
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Couple (or so) suggestions;
Make sure the ground connections to the chassis are clean and with good secure contact.
Make sure that the positive wire to the rectifier can't rub against the chassis, wear through and short out to earth. The first few inches of wire from the rectifier is prone to this.
Get a Harley Davidson or other third party compatible unit at greatly less cost and have it on the shelf (or in the boot) ready for the next time - much cheaper than one from MMC, just need to check that the crimped end that goes on to the main +ve connection under the bonnet is the right size for the connector.

The twin earth rectifier probably was a replacement!

AMC #288044 14/07/15 03:37 PM
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When I replaced the rectifier all bare metal contact areas were cleaned and after connection the area was greased and now ACF50 is in use. A plethora of cable ties should reduce the opportunity for wear, but your advice re the first few inches of wire out of the rectifier will be followed. Thanks.


Benfro Mog
AMC #288478 15/07/15 04:07 PM
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Can you post a pic of the rectifier please. Just replacing will not necessarily solve the prpblem

AMC #288498 15/07/15 05:03 PM
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Originally Posted By AMC
Has anyone any other suggestions to make regarding protection for this exposed and expensive item?


Return the replacement which I assume is the Cycle-Electric rectifier that S&S supplied.

Get the HD unit to replace it as it will be only a third of what you paid. Remove the rubber bobbins used to protect the C-E unit as they won't be needed. Bolt directly to the mounting point either in front like the older models or on the side.

Drive.

No bikers I have talked with have any respect for the C-E unit. It is supposed to constantly vary the current depending on load. They call it 'delicate' or a POS. The H-D unit just converts everything and dumps the excess to ground like all other bike rectifiers. Do one thing. Do it right.


What's your mileage? Who cares. Is it practical? See #1. What happens when it rains? You get wet.
AMC #288623 15/07/15 09:13 PM
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+1

Michael H #288650 15/07/15 10:53 PM
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Like Michael H says, bolt on a HD unit and end your rectifier problems. HD p/n 74540-01, easy and cheaper. AMC as for, "looking at how I can prevent the new one (£300- ouch!!) going the way of the first", I suggest you put it on the shelf in your garage. The problem is not that the CE unit is exposed to the elements, it is that it is, "delicate", or a POS. Buy an HD one for $50 on ebay and keep the CE one in the garage collecting dust, it's good for that.


AMC #289466 19/07/15 04:39 AM
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Originally Posted By AMC
I believe the latest M3Ws have the rectifier mounted along the length of the car, i.e. twisted through 90 degrees, but still mounted at the f/o/s (rhd M3W). Is this so?


I took a photo of what you speak of for future reference as mine is front mounted like yours. I've got new bobbins and a healthy cable tie around mine, but I will shortly pick up a HD unit.

Tally Ho ! And Welcome aboard ! thumbs cheers

Attached Images
Small New rectifier location.JPG (98.81 KB, 389 downloads)






2013 M3W # 793
'Mosquito'
Michael H #350774 26/03/16 05:20 PM
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Thanks, I'll follow this advise.


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Can I assume this is a combined diode pack and alternator regulator?

Also does anyone know the alternators output in watts or amps? - thanks.


Richard

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