The rebirth of Lazarus

[mickwinf]

I tried to check rectifier but not getting any readings, I do have a spare so will try that one. I hate electrics!

[taysidedragon]

Mick, if that doesn't do the trick do you have any electrical wizard mates nearby who can help?

[royhall]

Are you by any chance using a fully charged AGM battery. If you are, the charging probably won't cut in until the battery gets down to about 12.4 volts. Makes it look like the charging isn't working. There's a way of testing that explained in my CB750K5 restoration thread. Spent a whole day on mine pulling everything apart just to find there was nothing wrong in the first place.

[mickwinf]

hi Roy its a yuasa normal lead acid type battery. I am now looking for an idiots guide to using a multimeter, watch this space.

[Bryanj]

Mick, if you can wait till thurzday night (after you can ring me on 07795162623 and i will explain it to you, especially if you have the rec and meter in your hands


That should read after 8, i hate dumfones!!!!!!

[royhall]

It will still happen if your battery is fully charged even on a lead acid type.

Sent from my Pixel 7 Pro using Tapatalk

[mickwinf]

Thanks Bryan might take you up on that. Some progress with the rectifier, I didn't realise if it didn't read one way round one way try the other way round. This shows now as ok.

[mickwinf]

Looking again at alternator, the original one that came with the bike and the wires had been cut so put terminals on and extended wires to proper connector block. Thing is I dont get any readings at all at the multi connector but if i disconnect the wires at the joints I do get a result so maybe a faulty wire? The only spare I have also has the wires cut so no better. More investigation needed.

[Bryanj]

Did you scrape the varnish off the windings wire before you soldered?

[mickwinf]

I joined the wires under the sprocket cover

[Bryanj]

Go to Ash's emporium and look up the 3 phase charging system document that explains how the whole system works, plus ring me tonight and i will give you some testing to do

[mickwinf]

This morning I rechecked the connections and found a bad contact, sorted that then checked the voltage regulator which turned out to be ok, even tried a spare with no luck. the battery seems to hover around 11.5 volts when engine is running and does not increase with revs. rectifier tests out ok, again tried a spare with no change. not sure what to do next, any ideas?

[McCabe-Thiele (Ted)]

What is the voltage across the battery terminals with the ignition off?
Looks as if the alternator is not putting out any charge for it to drop to 11.5 volts when running.

I know now't about testing the alternator itself even after I have read the manual. In my case Impedence is a measure of my Ignorance.

Addendum:

I have had experience of electrical windings as in the coils/field windings absorbing damp and even recovering over time as they dry out. I know it's the often repeated mantra but good earthing & good electrical connections are a must.

[Seabeowner]

I've been lucky and all my rebuilds have charged fine. But your problem is not uncommon.
The goto in the US is Twotired.
Link to his post.
http://forums.sohc4.net/index.php?topic=118474.0

[Bryanj]

I am at work now and tomorrow night if you want to ring, after that not till next friday