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By Wayne
#7479
Hi All,

I have had my Lucas M01 mag / dyno renovated at great cost but has stood for 8 months while the bike was finished - now I have run the bike up the dynamo is not showing charge, having spoken to the company who did the the work I have tried re- polarizing it and have removed it and it will run as a motor when connected to a battery but when on bike will only show 2 - 3 volts output. Now I know you are all saying to return it but they took so long last time I am loathe to return it now the weather is good if it is something simple. Brushes all seem ok as do the wiring Anyone have knowledge ?
By Revband
#68731
To test the output voltage you need to link the D and F terminals together connect one voltmeter lead to the link wire and the other to the dynamo body. Do this with the D and F leads to the bike disconnected.
By Mark M
#68737
Wayne, it's worth knowing that the motoring test shows continuity of the windings but isn't an indicator of health in general! It could be that your dynamo has lost magnetism, that would explain the symptoms.

REgards, Mark
By Wayne
#68738
It would appear that I have been testing the unit in the incorrect way and it is giving output after all - thank you Revband - further investigation into wiring issues on the bike will take another evening in the garage - too hot to sleep anyway !
By Revband
#68741
Hi Wayne, happy to help and pleased it is OK. Mark when motoring the dynamo if done correctly D-F linked it will recharge the magnet.

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