discopaul

discopaul

New Member
Hi all
Ive fitted a new alternator to my 3.5 V8 and i dont seem to be getting any power from it. Since i have swaped this v8 from the N/A oil burner i had to re wire the cables for the alternator.

Im my pic the brown wire goes to the starter as ber the wiring diagram and the blue goes to the dash light. my problem was the wiring diagram shows the altonator as a cerceland not to which termainal on the back of the alternator. Also there are 2 spage connectors on the back of the altornator. what are these for?
 

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Paul, Its difficult to see in your picture if there are any markings near the terminals, but the fattest cable (which goes to the positive battery terminal, using the fat cable thats already come as far as the starter), should be attached to your alternator at the terminal marked B+
The smaller wire should connect to a terminal marked D+
But before you do, get a glamourous assistant to turn the ign on and watch the dash while you touch this wire to earth, the battery light should light up when its earthed. Just to check the wiring is all OK before you bin the alternator.
You'll find that all alternators have a few extra terminals that aren't always used, as the same alternater may have hundreds of different applications. For example, a 'W' terminal is used for tacho's/rev counters on diesels.
Hope this helps, Dave.
 
Also, make sure the alternator is bolted up tight, so the body of it is earthed properly. I see from your picture that the alternator bracket is painted, and this may cause earthing probs. Dave
 
Your right there are no markings .
Ive just been reading the manual and it says somthing about if the dash ligh has blown or not conected then the altornator will not work. also in the wiring diagram there is a restior. i did follow the wiring diagarm but the dash alternator light was on all the time even with the key out.
what sort of voltage should be made when at tick over?
 
At tickover with no load (lights off etc) then you want at least 13v ish, although tickover isn't really ideal for measuring output. raise engine speed to 2500 - 3000rpm and expect 13.5 - 14v. Then turn on as many electrical loads as poss (headlights, blowers, wipers heated screen etc.) and you should still expect at least 13.5v ish. Please don't take these figures as being Gospel, as it will vary from car to car, But you'll get a good idea of whether or not its charging the battery.

BTW a fully charged battery should read 12.7v when discconnected from car. so anything above this means its charging, but any less than 13.3/13.4v is probaly not gonna charge the battery quick enough.

Dave
 
I have a Yeasu FT7800R 2mtr/70cm Amateur Radio in me disco & when yu turn it on it gives you the input voltage it;s recieving Tis bloody great for checking ya alternator output. :D :D
 
sometimes the spade terminals are for connecting suppressors to earth - this could be one of the resistor items you are seeing in your diagram.

OR maybe the alternatpr will not charge without a resistance across the warning lamp circuit - thus, it has a resistor there too to up the resistance etc etc...

perhaps :D
 
Redhand

I do hope you have the required permit for the "voltmeter", but more importantly, what voltage does it say you get?

And does it drop when you TX?
 
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