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Alternator wiring
Freedo - September 18th, 2012 at 08:40 PM

Have had an alternator installed as part of an engine upgrade in my '69 bus. The seemingly simple connection of wires is proving difficult despite following instructions from some relevant sources.

It appears that a second red wire from the front side of the firewall was not connected to the regulator in the previous setup. Have now connected an additional wire from the solenoid to the front of the alternator as outlined in some resources - but the warning light remains on and the battery doesn't hold charge.

I am looking to head for an auto electrician but thought I may be missing something glaringly obvious. Any help would be appreciated.

Cheers,
Mark


Klaus - September 19th, 2012 at 04:14 PM

you can go either way , pos from batt to alt or pos from starter to alt , the wire that goes back into the loom to the front of the car orig from the regulater goes to the black plastic part brush holder on alt as the batt light, unless you have an older external reg alt with 3 male spade fittings on top and the alt/power wire fitting
if you cant work out which wire for batt light look at dash lights and take out bulb n holder to see what colour the wire is , think its solid blue for batt , blue /green for oil , blue red for ind , blue /white for high beam


Freedo - September 19th, 2012 at 09:52 PM

Ta for that. Had a discussion today with another AVD member and checked out a few things he suggested.
1. Power to light on dash when ignition on - ceases when DF connection is removed - so all good there
2. 12 volts at D+ when connected to battery - doesn't seem to get much more when engine cranked, however.

Still cannot see a second red wire coming from the loom that should have previously been attached to the regulator. This seems to be a missing link but cannot understand how it all would have worked before without it?

Need to call an expert to take a look me thinks.


68AutoBug - September 20th, 2012 at 02:08 PM

Quote:
Originally posted by Freedo
Ta for that. Had a discussion today with another AVD member and checked out a few things he suggested.
1. Power to light on dash when ignition on - ceases when DF connection is removed - so all good there
2. 12 volts at D+ when connected to battery - doesn't seem to get much more when engine cranked, however.

Still cannot see a second red wire coming from the loom that should have previously been attached to the regulator. This seems to be a missing link but cannot understand how it all would have worked before without it?

Need to call an expert to take a look me thinks.


what Do You mean doesn't get any higher when engine is cranked??

when cranking You engine [turning it over] the voltage will go down as the starter motor draws a huge amount of power from the battery

when running, the alternator should be charging about 14 volts at least...

LEE


Freedo - September 20th, 2012 at 02:53 PM

Meant 'running'

Cheers


southspark - September 20th, 2012 at 04:45 PM

Is your alternator internal or external regulator.Have a look how many terminals are on the alt & what letters are marked on them ,eg B+ Df etc.

Paul


68AutoBug - September 20th, 2012 at 05:52 PM

Is it an internal regulator alternator in which case it will only have two connections

B=battery

and the smaller terminal that goes to the dash lamp..

My Bosch alternator has the screw connection to the battery

and the push on terminal goes to the dash lamp


http://inlinethumb63.webshots.com/49278/2772327340050767931S500x500Q85.jpg

LEE

external regulator alternators have an external regulator..
with two or three connections plus battery terminal on the alternator and cannot use a generator regulator Lee


Freedo - September 20th, 2012 at 09:25 PM

Thanks to all who have responded.

To clarify - internal regulator. A few more conversations today would suggest wiring OK. I am off to the local autoelec tomorrow for an assessment - may have jagged a faulty alternator?

Cheers