fitting new alt regulator- extra wire?

[slowcoach]

hi!
ive had an overcharging alternator, boiling the battery nicely at about 16/17 volts. however the battery sees to have survived, im fitting a new regulator. i got the part from a bristol auto electrcal place, giving the bosch alternator part number. its a 90amp unit. ive got the alternator out, and also the regulator now- but now ive taken the reg out, there is a short red wire attaching the regulator to the inside of the alternator body, soldered at both ends.

i thought it would just be a 'pull out and replace part' job, but the exisiting regulator is clearly 'hard wired in'. the wire comes off one side of the regulator, and into the body of the interior alternator to what might be an earthing point perhaps .. though it is a red wire.

the replacement regulator is the right size etc and looks ike itd go right in. any ideas? is this a mod to 'trick' the alternator ive heard of?

cheers

[slowcoach]

managed to get a couple of photos up of it-

hope this helps! We're away on holiday and are meant to be leavng today! always a complication isnt there

http://www.flickr.com/photos/61277093@N ... 343767155/

[Oldiebut goodie]

You're right in that it looks as though it is an earthing wire - it looks as though it should have a spade terminal to clip on the regulator. Just check the continuity of it with the alternator body with a multimeter.
Has the new regulator got the spade terminals on it?

[slowcoach]

thanks oldie-
yes, not having a spade terminal or even a blank spot to solder onto on the new regulator threw me a bit. after a bit of reading and 2 phone calls, ive learned that it is taken from the field coil brush of the alternator, and likely leading to some sort of emf supressor somewhere. something usually found on service vehicles, where some major electrics have been added, like a tipper or air con or something apparently, to take away any possible surges? this is possibly to help protect the ECU perhaps on my van. anyway you can tell im no expert, but i ended up replicating the connection on the new regulator and its in and working now...
learn something on every job huh!

thanks again-
john.

[bigherb]

There should be a spring contact there. Looks like yours has broken off and been hard wired.

[slowcoach]

There should be a spring contact there. Looks like yours has broken off and been hard wired.

ah, for a spade connector or something?

incidently, the only way i noticed my battery was getting boiled while driving, was that my windscreen wipers were working extra fast cause of the 18 volts or so, and a slight funky smell of ammonia.. lucky it was raining really! once i stopped to check things out, i could hear the battery bubbling.

[bigherb]

ah, for a spade connector or something?

No the spring contacts the regulator once it has been screwed in and works like you wire.

[slowcoach]

ah ! good news then- much appreciated