3 wire alternator question

i have just finished wireing my alt up on my car. new alt 3 wire, new battery.my question is .i wired up the 18 gauge wire from the back of the alt directly to the battery .i jumped #2 over to the bolt going in series with the 18 guage wire .now as for the #1 prong on the side of the alt i know that goes from the switched 12 volt source on the ignition to the #1 prong on the side of the alt in series with a diode and or a dummy light. i didnt run a diode yet or a dummy light i just wanted to check and see if the battery was chargeing so i started the car let it run at idle for a couple minutes than turned the car off .well at 1st when the car was turned off i realized because i didnt run the diode the car stayed on ..so im p***ed that point ..i know i need a diode what is the part number for this diode..and 2nd the battery wont charge what could i have done wrong..alt is brand new and so is battery..HELP

 

do a search on here for the diode part number (i cant remember), i always use a warning light. with the wire hooked to the ignition source is it charging?. also i would run a 10 gauge from the back of the alt to the battery (fused of course).

 

im sorry i did use 10 gauge...no it is not charging at all unless i jump the car it wont start and than when i shut it i cant re start it..its dead

 

This should help , what i've done is the 1+2 terminals can be wye'd together to a switched (key on) wire and of course the screw stud terminal is hot at all times like you did
http://madelectrical.com/electricaltech/delcoremy.shtmlI am ***uming it's internally regulated?

 

did you forget to run a ground wire??

http://www.hartin.com/alt.htm

 

im a little slow i dont understand what you did.

 

well the alt should be grounded to the block no...i needed a ground also ...??

 

i always run a ground to the case, i would use a alligator clip and put #1 to the 12v feed and check the charging...if it's still not charging then the alt is no good.

#1 goes to a warning light or diode
#2 goes to the rear 12v post

 

i didnt ground the alt because i thought it would be grounded threw the bracket ..but i will try to ground it a.s.a.p as far as the diode
i just want to make shure i got this correct run #1 post inline threw a diode inseries to switched 12 volt

 

the ground wire is just in case..............

http://www.jalopyjournal.com/forum/showthread.php?t=324824&highlight=alternator+diode

 

If the #2 is going to the 12v post can it ust be wired to the + on the alternator

Can i wire from #1 to diode to fuse to light bulb to coil

 

This is what i did also! No diode, no idiot lite, just 2(plug wires are tied together) simple wires actually.its been working on mine for 11 yrs, 48,000 miles.
No need to ground it the bolts do that for you, just ground the block to the frame.
JimV
Just remember the "K.I.S.S" rule! "Keep It Simple, Stupid"

 

Just in case you used powder coated brackets. You will need a ground are grind some powder of to get one. $0.02

 

lol ..nope no powder just black paint..i just cant figure out why it wouldnt charge ive been thinking about this all day since i left it ...

 

so is this how you have it wired? run a jumper wire from the number 2 terminal to the battery terminal, and then from the battery terminal to the battery, this is hows it's done, you have to rev your engine to about 1200 rpm's before it will start charging, i just start my truck and drive so it starts charging as soon as i take off.

 

i do have it jumped like that but i also have a hot wire from the ignition to the other post #1and nothing than ran it your way also and drove it up the block came back shut it off and tried to start it and nothing brand new battery dead ..

 

i have no wire on number one. i have done this on 5 different vehicles, you could have a bad alternator, once i have the car running and reved to get it charging i just pull the negative cable off the battery, if the car keeps running then the alternator is working, if the engine dies then it's not working, others may tell you this might hurt your alternator but i have done this 100 times without any trouble.

 

ok so later on today i will go back and run the #2 prong jumped to the battery nut on the back alone ..start the car rev it for ill give it a couple minutes and than remove the ground on the battery if the car shuts the alts no good.
im going to disconnect all the fuses to make shure nothing is drawing power except the ignition just to be shure ..hope this works

 

hey 440 i have tried it this way without the diode still no charge

 

How do you know it's not charging? Are you checking it with a volt meter? Or is the car just having trouble starting back up?

You could have a problem with the wiring to your starter, bad ground? Loose battery cables? Could be a couple of things.

 

yes that's exactly correct. its only been done one billion times.

 

hey zombie i checked all the leads to the fuse panel,checked the termianls ,checked fuses ,the only way it will start is if i jump it im going to get a voltmeter today and check it out ..

when i put the charger on the battery to jump it there is a meter on the battery charger its very low less than i belive 20 amps. video was cool as **** too ..thanks and even my gurl who dont like hot rods liked the movie..

 

i like to run a warning light so i know when i'm screwed and to find a place to stop or limp to. without anything you'll know when the car dies and won't crank over again. also i wouldn't recommend getting a feed for the alt trigger wire from the coil.

 

Yes and all diodes operate at a .7 voltage drop ( reading 11.3 ) so the alternator thinks the battery is not fully charged and will overcharge it. A very common problem. Use an idiot lite for resistance and you eliminate that potential problem.

 

ok so today i went back and check everything ..i bought a brand new volt meter took the battery back to get it tested and its good.i jumped the car again started it up and let it run at about 1000 rpm's shut it off and tryed to re start it and same problem nothing until i jumped it ...at this point i was sick and tired of this problem so what i did was remove the alt and took it over to the local ace electrical and had it checked they said the alt was good but the problem was that i would not be able to charge the battery the way everyone is saying to do ..so they took the alt apart and made it so all i had to do was run the 10 gauge wire back to the battery without a diode and without having to jump #2 post to 10 gauge ..so i took the alt home put it in the car started the car let it run again checked it with the volt meter chargeing at 14.3 volts thought i was good shut the car went to restart and nothing .the battery was still dead wtf am i not doing correct ..i even checked the battery with the car running 13.9 volts but still not enough to crank the starter .....

 

so without the engine running what do you have for voltage on the battery? sounds like your starter might be dragging, so what did the shop charge you to work on your alternator?

 

i think the battery has 12. with out running 20 bucks to make it self excite..
what do you mean dragging you mean draining the battery ..

 

if your battery is fully charged it should read 12.5 volts around there, sometimes when starters get old then can drag, what thats means is they take more power to turn over, so by jumping it you adding more amps, maybe your battery just is not heavy enough to turn your motor over, do you know what the cold cranking amps of your battery is? if your battery is heavy enough your next step might be to take your starter in and have it checked.

 

hey budd.the starter is brand new the cold cranking amps is 650 and normal cranking amps is 525

 

well, do you have a battery charger?, i'm just thinking your battery is just not charged up fully, or you could hook up your booster cables and let the battery charge that way, is there a chance your starter needs some shims?