Im running a stock alternator on my SB and im having a problem with charging. I use an electric fuel and water pump along with an electric fan. The alternator is pushing around 11 volts and I know it should be 14 volts.
What alternator should I run?? How many amp alt. should I get?? Ive heard alot of people have switched to a 1 wire alt,why??
THANKS!!
Posted By: MR_P_BODY
Re: ALTERNATORS - 04/13/11 09:31 PM
Add up your amp draw then add a extra 15%, that would
be what I would use as a minimum(more takes more power
to turn)... most of the guys like the 1 wire because
its easy to hook up... myself I dont care for them...
if it has a regulator problem you either buy a new one
or tear it apart and fix it... it you have a external
you buy a reg and your back on the road.
At 11 volts you have a problem... full field the reg
and see if the alt is putting out
Also when I say all of the draw items that means
lights and everything
When I put the lights on,the volts drop to 10. I dont have any of them hooked up with relays,would that help if I did that??
Before I put on the electric water pump and fan,I was ok but now,im not.
Posted By: earthmover
Re: ALTERNATORS - 04/13/11 11:15 PM
hey mike when i was having problems with the chargeing system mr.p and some others gave me some good advice...i redid all my woreing from pump and fans and also went with relay on it all problem solved with the stock type alter...i had holley pump,electric fan, and water pump drive and would have to change battery at the track after about 3 pass then fixed wire and no problem with the battery but i still put a new 1000 cc init...mike
Posted By: Anonymous
Re: ALTERNATORS - 04/14/11 12:26 AM
I have an extra east coast 1 wire mini alternator new if you want to go that route. they work great. pm me if interested.
Posted By: Bad340fish
Re: ALTERNATORS - 04/14/11 12:43 AM
I used a late model GM alternator. I honestly can't remember the series. It works well even with a underdrive pulley. It charges at 14.4 volts with all accessories on at anything off idle. I also eliminated all of my stock wireing with the exception of the lights and wipers.
Posted By: Just-a-dart
Re: ALTERNATORS - 04/14/11 02:32 AM
Mike I run a 90's style denso alt. from a dakota, they come in 90 120 or 140 amp and use a 2 wire external field and charge well at a lower rpm. You can use a mopar 72 up style regulator and it works great. Mr P is right you have to have more altenator than load or you will have to charge the battery, this can be ok for a race only set up but not for me. One of the good things about this alt/reg set up is you can buy the parts anywhere when ya need it. There is a lot to the 1 wire vs ext. field ask if you want more info. Hope this helps.
Posted By: ahy
Re: ALTERNATORS - 04/14/11 03:13 AM
With an electric WP, FP and fan you don't have a chance with a stock alternator. I'd guess you need at least a 120 amp unit. I'd consider a 120 amp Denso or a 140 amp Powermaster GM based MOPAR adapted alternator. I'm not real knowledgable on SB brackets and clearance but the 140 A Powermaster unit (Summit) may be a bolt in with stock brackets.
Upgrade of the charge wire as a minimum - 6 guage to fender relay or battery - is needed to run the bigger alternator without meltdown of wires and the bulkhead connector.
Posted By: Quicktree
Re: ALTERNATORS - 04/14/11 03:16 AM
Mike charge and have the battery checked before you go changing the alt.
you can also take the alt off and take it to the local parts store and have it checked.
Posted By: Bad340fish
Re: ALTERNATORS - 04/14/11 03:29 AM
I had an upgraded(80 amp) stock alternator and known good battery and still had constant trouble when trying to run everything electric.
I think that alternator would have been fine had I bypassed the amp meter and the bulkhead connector the first time around. Instead I just made double sure and went for an even better alt and took out ALL the factory wiring that had to do with the charging system.
Bieng how I manage a battery distributorship I can't take any chances on bieng dead in the lanes again lol.
Posted By: Dodgem
Re: ALTERNATORS - 04/14/11 01:58 PM
I bought a 120 (bottom left corner) at mancini's and wow sold my gas generator after. you cam phone and buy the alt seperate
Posted By: Crizila
Re: ALTERNATORS - 04/14/11 03:27 PM
Weather you run a one wire or the stock external regulator set up, it won't make any difference in regards to alternator output. If you are running a stock alternator / pulley set up, you probably won't have enough juz at idle ( even if everything is up to snuff ). Between the fuel / water pump, fan ( your biggest draw ), and ignition alone you are probably pushing around 60 amps. No stock Chrysler alternators can push that number at idle ( below 1000 engine rpm ). You could try going to a smaller alternator pulley ( unless you already are running a 2.5" pulley which is the smallest you will find ), a larger crank pulley, or buy a later model alternator ( Denso, etc ) that has a high rise time - more juz at idle. I ran in to similar problems as you, and my schedule calls for 3-4 night races ( add lights ). I also race at some pretty high temps here in the AZ area. I dumped my electric fan ( saved 28 amps ) and now run a large 19" flex fan - cools better also. It cost me about a tenth, but I don't have charging or cooling problems. I run a 1 wire Chrysler style alternator ( square back ) with a 5" Moroso pulley on it.
Posted By: jbc426
Re: ALTERNATORS - 04/14/11 05:29 PM
I also used a late model GM AC Delco alternator, the CS144. They're used in Escalades, Suburbans etc and put out some serious amperage at idle, in the 115amp range at idle and The one I have was rewound and peaks in the low 200 amp range at fast idle. It's internally regulated too.
There are $35 adaptors available to adapt it to the stock Mopar brackets. You can see it in this pic. I'm using the Buschillon hidden a/c bracket hardware and rerouted the drive belts on their system to increase the radius of belt to pulley contact; but it all bolted right in nicely.
It's not yet the most popular conversion, but it is the best bang for your alternator buck.
Posted By: Bad340fish
Re: ALTERNATORS - 04/14/11 05:36 PM
Thanks to the above post I remembered what my alternator was. Its a CS130 GM.
THANKS to all for your info and advice.Hopefully I will have my motor back together in a few weeks and then I will do some investigating and hopefully get it charging like it should.
Posted By: sshemi
Re: ALTERNATORS - 04/15/11 09:13 PM
i wouldnt want to run a high amp (60+) alt through the stock amp meter.
I dont know how these onewire alts work but if they sence the voltage through the B+ and you run it through the stock wiring there will be a lot of voltage loss witch will make the alt to overcharge the battery.
Sure high amp are fine but you need the wiring to handle it also.
Posted By: Bad340fish
Re: ALTERNATORS - 04/16/11 05:26 PM
Hmmmm I don't see why not. Its just a flat piece of aluminum, they did machine some areads for the bolts and a small recessed areas for adjustment bolt on the alternator. I don't see them bieng a problem if they are on the backside. I will be out in the garage today and the bracket is off the engine right now, I will take a look.
Posted By: mhead
Re: ALTERNATORS - 04/17/11 01:40 AM
had same problem few years back.stock mopar charging goes through your amp meter (NOT GOOD)get a volt meter gauge either way you go.I went with a powermaster 1 wire(part #8-475229)140amp.car pick up .10 Just run 6 gauge wire from alt. to starter.
I do have a volt gauge,thats why I know it only puts out between 10-11 volts.
I hope to get it running again SOON!!!!!
Posted By: 69CHARGERMD
Re: ALTERNATORS - 04/17/11 10:37 AM
Just went thru this with my car. 11_12 volts at idle,,,, worse as I turned on the fan, water pump etc was killing my battery,,, etc. my alt was bad,,, I had a one wire, but upgraded to a three wire to get the sensing function. 60 amp denso alt from mancini with the bracket kit,,, it is actually a toyota fore runner alt,,, that is being used for mopar race applications,, it fixed my problems,, now I have a steady 14 volts and the volt meter doesn't even flicker when I turn on the fan, water,etc. I can post the part number if you need it.
Can you PM the number so it doesnt get lost?? Thanks!!