charging system upgrade

Discussion in 'Injection Tech' started by terra firma, Mar 4, 2008.


  1. terra firma

    terra firma Farmall Cub

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    When striping down the wire harness from my donor 91 GM C1500 I came across the harness for the GM CS type generator. Looking at the service manual they are rated at 85-105 amps. Has anyone used these generators?The manual does state they are CW rotation, I have not looked what the rotation is on the scout.Would a higher amp generator be required ? I would think It would not hurt to have more output.
     
  2. Bill USN-1

    Bill USN-1 Moderator Staff Member Moderator

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    It's an option you can do but it is not required.
    The 3 wire gm alt that is stock on the scout is a very good system if wired properly.
    See madelectrical for tips on proper wiring.

    If you are running a lot of accy like a winch or big stereo or big off road lights, then you may want to upgrade to a higher output alt.
    I simply installed a 105amp kit in my stock alt and called it good after relocating the sense wire.
     
  3. EagleMark

    EagleMark Banned

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    EFI does require a good charging system. Start with a quality battery then look to see what alternator you have. A 63/65 amp is what comes on a Scout with A/C (dual pulley). Without A/C it's a 38 amp (single pulley) I believe. Unless you have a 79/80 Scout II with improved wiring and bulkhead connector you should read the FAQ on upgrading the wiring for the charging system when you upgrade alternators.
     
  4. larboc

    larboc Binder Driver

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    I agree, the 3 wire GM style alternator is simple and works great, provided you don't try to use too big of one and burn out your through firewall connector and spend months chasing your charging problem. rant off.

    anyway, I bought my reman 85amp delco style for 18 bucks from carquest (nice to have friends behind the counter)

    go price a new style.
     
  5. Dave Clifton

    Dave Clifton Farmall Cub

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    In reply to your question, yes. With the proper adapter ( from NAPA) you can run a CS alternator. I run a CS144 with the stock Scout mounting bracket. I also have a winch, aux lighting, an electric cooling fan, and A/C. Thus I desired more amps.

    Oh, and I have also performed all the Mad Electrical improvements and upgraded the bulkhead conn, et. al...to handle the amps. Would not try the bigger alt without doing so.
     
  6. RD Durham

    RD Durham High Wheeler

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    Either the stock Delco SI or the Delco CS alternators will work with or without EFI. The stock Delco 12si alternator can be found in amperages up to 94 amps stock and can be pushed to 105amps on a custom build. You can swap up to the Delco 15si or 17si and get amperages up to 120amp. While the Delco 15si and 17si alternators are slightly larger than a 12si they are essentially a bolt on swap. I've run both the 15si and 17si alternators with 120amp ratings.

    You can also run a Delco CS alternator on a Scout. I'm now running a Delco CS144 alternator that is rated at 140amps on my Terra with TBI and a CS130 105 amps on my Traveler diesel. I would look at only a CS130 or CS144 and stay away from the CS121 or CS130D as they have some issues that don't allow them to be very forgiving. To run a CS style alternator you either have to rewire for a CS style plug or purchase a SI to CS pigtail adapter, about $25. Advantages of a CS over an SI alternator are that the CS alternators charge at a lower RPM than the SI alternators, have better cooling and can be found in higher amperage ratings stock. Disadvantages are that you have to rewire (though with an adapter pigtail it's not an issue), CS alternators cost two to three times more than SI alternators (but you can find CS alternators fairly cheaply in an auto salvage yard), you have to find a CS alternator with the correct housing, a CS alternator won't charge if the battery voltage falls below a certian level of voltage, and CS alternators are a little more difficult to rebuild. The low voltage no charge issue is a protection device to protect the CS alternator from going to a full charge, and possibly burning up, on starting the engine when you have extremely low battery voltage. It's a pretty low voltage and is usually only an issue if the battery is completely drained. If your jump starting you just keep your jumper cables on a little longer to make sure the CS alternator will stay at full charge before unhooking.

    As noted, if you are not running a high amp stereo, off road lights and/or a winch then swapping to a higher amperage alternator really isn't necessary and a stock Delco 12si alternator is all you need. If you swap to a higher amperage alternator it is imperative that you also upgrade your charge wiring at least with a shunt wire or you will almost certainly end up with melted wires and/or an electrical fire.

    You can also check out this thread.

    Delco CS130 Alternator Installation
     
    Last edited: Mar 5, 2008
  7. Eric VanBuren

    Eric VanBuren Lives in an IH Dealership

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    The CS alternator was designed with FI in mind it does have a much tighter voltage control to keep the computer happy. The disadvantages are the price and the fact that they are packing so much amperage into such a small case they can have a shorter service life than a stock SI of similar output when called on for full output frequently.

    If you do swap in a CS or any other alternator than a stock 10si be sure to bypass the BHC with a wire rated for the amperage of the alternator.
     
  8. terra firma

    terra firma Farmall Cub

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    Thanks for replys,I will look into upgrading wiring system, the plugs aren't a problem, I already have them. The reason I asked, was because I can acquire the CS type generators free. Just have to find the right one.
    Thanks again.
     
  9. jlynch

    jlynch Farmall Cub

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    .


    Might be a dumb question but what is a shunt wire? Also what size wire would you need for a 105 amp alternator?
     
  10. Eric VanBuren

    Eric VanBuren Lives in an IH Dealership

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    In this case shunt wire means to run a wire directly from the alt B+ to the starter B+ so that the current to charge the battery does not have to go through the stock wiring that was designed when 37A alt was standard.

    As to wire sizing it depends on how long the wire is and who you talk to. 6ga is a good choice for 105a, 8ga is marginal depending on the length.
     
  11. jlynch

    jlynch Farmall Cub

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    Thanks for the info, the reason I asked is I am about to do this upgrade on my Jeep. I have a cs130 which is 105 amps, I also have the correct adapter plug with the resisitor built into it. I also read somewhere else that you should have a fusible link on the wire going to your starter or starter solenoid. Is there any truth to that??? I know my stock alternator wire has a fusible link at the starter solenoid.
     
  12. Mike Elrod

    Mike Elrod Farmall Cub

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    I run a Caddy CS 144 alt and I've got an onboard welder. I run Two alts, one for the welder and one for the electrical system. They are completely independent of each other. The welder is a Premier Power welder set up. I burnt up a few Premier Alts so now I just run a Large ford alt(they are $15 on 1/2 price day at P N P) that I wired into the Premier system( should have done that along time ago). I excite the welding Alt on a toggle switch.
    I usually pick a couple of the CS alts up on 1/2 price day and GIVE them to my Buddies and help them hook them up, cause I'm tired of their charging problems:punk:
     
  13. R290

    R290 High Wheeler

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    Are you using the Ford G3 or G1 for your welder? G1 has external regulator.
    I looked high a low for a cs144 but they were always gone. Decide to just put a Ford G3 130 in there as they can be found any day of the week. going back for more stuff I found a cs144, of course now I find one.
     
    Last edited: Apr 2, 2008
  14. Mike Elrod

    Mike Elrod Farmall Cub

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    I'll take a pic as soon as I get a chance.
     
  15. R290

    R290 High Wheeler

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    I doing the MAD electrical changes to my Scout. High amp alternator, start'em up kit, amp meter by pass ( move wires to 1 lug) and idiot light. I have installed most of it, just need to figure out if I can use the brown/white resistive wire as the idiot light wire too. I doodled on the MAD drawing a bit too.

    [​IMG]

    Mike looking at the Perimer Welder site I can see which alternator they use. Would still like to see a pic on how your dual alt. system is belted up :)
     

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  16. Eric VanBuren

    Eric VanBuren Lives in an IH Dealership

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    There is no reason to wire it per the MAD diagram. It's just a way to replicate something GM did to save money 40 years ago. IH improved on the SI wiring by using the ammeter as their junction and locating the Volt sense wire at the starter soleniod. Eliminate the CN-1 junction block and connect everything to the new Ford soleniod. There is no magic "minimum" charge wire length, the shorter the better. On many 2000ish GM vehicles the alternator power wire is only about 1ft long and it bolts to a tab in the middle of the +battery cable on its way to the starter. If you don't want everything connected to the Ford soleniod run a wire from it to the CN-1 to power your new power needs, but run the alt wire to the Ford soleniod.




    The resistance wire can be left in and used for the charge indcator lamp feed. I have done it several times, the first time quite by accident and I didn't relize it untill many years after the fact when I wanted to add a idiot light when I bypassed a failing BHC, and it hit me. With one alternator I had a situation where the light would glow sometimes, not enough to really notice during the day but obvious at night. I use the P.brake on/ axle engaged light as my idiot light, in some years and models it is a plug and play operation others you may need to change the connector or splice the wires, the most basic models will need another pin installed in the connector to the speedo.
     
  17. R290

    R290 High Wheeler

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    Thanks Eric. I did a lot of digging through cars and trucks at PNP this week looking at how different models were configured. I grabbed a terminal block off an 89 Chevy truck and noticed that all the wires connected to it are fuseable links. I looked at few Fords too, all in the late 80 early 90's Some use a mega fuse. I like the idea of all the power going and coming to one location., except the starter wiring. It's just that I'm doing it all at once, so there is a big learning curve. I can't believe my Scout never caught fire, the P.O hack into the wiring everywhere. Even pulled out some solid house wiring too, they cut insulation off a lot of wires trying to troubleshoot issues.:death:

    Reading on the Optima web site they say no amp limit as long as the battery is under 125 degrees. Never measured my battery temp before. I just picked up a couple double 12 gauge fuseable links off a Ford with 4 gauge wire attached to them about 2' long, I can use it for the link to the solenoid "charge wire" taking it from an 8 gauge to 4 gauge.
     

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