Alternator q

[shmoov69]

How do I put a late model alternator (90's GM) on my 69? It is not a one wire on it now, I think! But I can't quite remember!:scared:
THnaks

[matty b]

There are two ways to do the conversion and one I think is ugly and the other way is the way I do it. The clean way you need to open the harness up from the external regulator over to the original alternator plug on the motor. What you need to do is strip out the white and blue wires going from the alternator to the regulator plug. After that you need to take the brown wire that is hooked to the regulator connector and route it over to the alternator itself. You should have enough length if not solder on a section of wire to get it there although if you maintain a drivers side alternator this shouldnt be necessary. This part is optional but I say that it is essential considering that if you dont do it you are sorta defeating the purpose of upgrading the alternator. If this is over 100 amps and it probably will be then I suggest running an 8 awg power lead from the battery to the alternator bat stud. DO NOT just run an 8 awg from the horn relay over to it because the bat lead feeding the horn relay is a 12 awg lead so it still is undersized. Also you need to install a 6 inch length of 12 awg fuse link at the battery to the alternator bat lead. This ensures that if this wire shorts that the fuse link will burn out prior to the wire melting. This is mandatory so dont skip it. Fuse link can be baught at NAPA for a few bucks and its well worth the price. Ok so if you decided to run in 8 awg the what you want to do is trace the bat lead from the alternator back to the splice it makes around the horn relay. Cut the wire out at the splice but remember to maintain the splice for the other wires. Tape the short little stub of the wire up where the original friction tape is for the rest of the splice. Ok at this point you have all the wiring set up for the alternator. Make sure you swap on the pulley from your original alternator to the new one so that the belt will fit correctly and bolt on the alternator. Hopefully the alternator is clocked correctly on the back so that it is the same as the original if not find someone that knows how to clock the back since it takes a bit of skill to keep the brushes in place when you turn the back of the alternator. Ok now on to actually wiring it. You should have two wires on the connector that you need to hook up. There will be an I and an S or F leg. The I leg gets spliced to the brown wire and the other wire you need to loop over to the battery stud on the alternator. Hook up the battery lead to this stud as well and youre done. After that make sure the belt is tight and tape the harness back up. Now you can throw away the external voltage regulator and the wire you pulled out. This take me about an hour to do start to finish but for a newbie to it should take about 2-3 hours to do correctly. Hope this helps and lemme know if you have anymore questions

[6'9"Witha69]

This should help out . . . http://www.madelectrical.com/electricaltech/chevymain1.shtml

[shmoov69]

Well! That sounds a little long! LOL! But simple enough. I do appreciate the info! I think that I ditched the external regulator years ago, but I can't remember. Heck, I haven't done much to it in the last couple years, so that makes it even worse on remembering what was done! For the plug into the alternator, can I get one from the parts house or is it a dealer only or salvage yard item?
The alternator is a 140 amp from a SyTy truck BTW.
Thanks! And I will prolly have a couple q's when I go to put it on!

[6'9"Witha69]

It is probably a normal part from any parts house. 10/12SI model.

[matty b]

yeah its a cs130 alternator, cheapest way is to go to a pick n pull and grap one up. Just remember that the brown wire is igniton and triggers the alternator to turn on. The other wire is a battery sense leg and it reads how much voltage is being sent out.

[shmoov69]

Thanks guys.