11 replies to this topic

[RonH]

Hi all,
I need to run this by some experience just to make sure I'm not being stupid...
I have a brand new 70 amp alternator from minisports. The problem is its not producing any power.
I have a good earth strap and a brand new wiring loom. The fan belt is new and tight, battery is good and I have battery voltage at various spare terminals on the alternator.

Anyone have any suggestions of what might be wrong other than it being a duff unit?

Cheers
Ron

[Dan]

  Is the charge warning lamp working?  The bulb hasn't failed?

[KernowCooper]

Here are the alternator test to carry out to see where the problem lies http://www.theminifo...ng-basic-tests/

[RonH]

Is the charge warning lamp working?  The bulb hasn't failed?

Hi Dan, thanks for replying.
I have an ameter and voltmeter fitted instead of having a charge warning lamp.
I started off leaving the charge warning lamp wire disconnected then used it to test for output using a voltmeter. It did not register any voltage or current when I started the engine.
Does this need to be connected to live, and if so, directly or through a bulb?

Ron

[KernowCooper]

The charge light supplies a exciter voltage to the alternator to start it charging, there are some alternators that do this internally though, what alternator is yours?

 

Have a read of this about how the ignition lights work http://www.theminifo...g-how-it-works/

Edited by KernowCooper, 06 August 2013 - 10:06 PM.

[lrostoke]

you need the charge light connecting or the alternator won't work...

 

one side of the charge light goes to an ignition switched 12v live, the other side goes to the small spade terminal next to the 2 large spade terminals (probably already knew that, but safe than sorry)

[Dan]

  As above if it's a Lucas alternator then the warning terminal needs to be connected, through a 2.2W bulb, or it won't generate. You may have damaged it by running it disconnected but as the main load cables presumably were connected to a battery it should be OK. If you had it connected to nothing at all you may have fried it.

Edited by Dan, 06 August 2013 - 10:14 PM.

[RonH]

Hi and thanks for all the replies.
I"m not sure who made the alternator, it"s not the standard Lucas item but the 70 replacement from Mini Sports.
It"s too late now to run through the checks (thanks Dave) but I"ll give them a go tomorrow, and try connecting the charge indicator though a 2.2w bulb to see if that helps.
Cheers
Ron

[Dan]

  The 70 Amp type are Lucas A127 units.

[KernowCooper]

If its a Blade Type then its a direct replacement for a 17acr type of plug

[RonH]

Well that sorted it!!
Went through the checks (thanks Dave): wiriing was fine except I had the charge warning wire connected directly to a switched live not through a 2.2w bulb. Added the bulb and ...vroom...14.8V
All I have to do now is work out how to include a vintage 2.2w bulb in my high tech LED style dash display!
Other than that, I am now in a position to get the dash in and fit the windscreen > full going car [Yeehaaaa!] 3 years in the (re)making.
Unfortunately I'm off on holiday this evening so it will be on hold for another 2 weeks but what's that in 3 years!!

Many many thanks to all who contribute.

Ron

[Dan]

  You just need something of the same resistance.  A resistor would seem to be a good idea.

 

  If you search the site you should find a diagram of how to use LEDs as the no-charge warning.  We discussed it some time ago.  If not then PM DK Lawson, he will remember the layout.  Basically you need the right resistance for the alternator, the LED itself as a warning lamp, and blocking diodes to protect it.