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Need more ALTERNATOR power!

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by TopOff, Apr 13, 2004.

  1. TopOff

    TopOff 1/2 ton status

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    [ QUOTE ]
    Damn IT SCOTTY! I need MORE POWER!

    [/ QUOTE ]

    DAMN these ELECTRIC FANS!

    I killed my gel-cell three times this weekend! I put it on a 2 amp trickle charger and the battery was fine in a 1/2 hour. So I doubt it'ss the two year-old battery.

    I thought I killed the alternator. I had a trail-spare, put that on, still not enough charging power. Then I thought maybe my battery Isolator was bad. I bypassed that (killed the battery isolator with it running). /forums/images/graemlins/frown.gif

    IIRC- the alternator for a '73 was only ~60 amps.

    It's not enough power to keep everything going.

    Anyone know what year/model I can ask the Kragen/Autozone guys for a 100 amp (or 90) alternator that will use the old style belts?

    For some reason I thought it was a van but I am not sure of the year. :unsure:

    Thanks.
     
  2. jakeslim

    jakeslim 1/2 ton status

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    i just installed a Delco #729012 last month. Cost 89.99 and is either 108 amps or 120 amps. I've seen it at both numbers online, but either way, plenty of charge. I fit on the bracket also. I returned my old 60 amp and got the core back no problems. i installed it on an older 350 block so it should work for your application(v-belt)

    by the way this was at Kragen
     
  3. TopOff

    TopOff 1/2 ton status

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    Do you know what year and model that Delco is out of. My Autozone guys might help me, but I am pretty sure the guys at my Kragen won't.... /forums/images/graemlins/frown.gif
     
  4. jjlaughner

    jjlaughner 3/4 ton status

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    THere's a seller on ebay that sells hi amp alt, built to order... I did have one problem the first time he sent me the wrong one, sent it back and got the right one the second time, its 60 amp at idle and 130amp alt for $75.99 (I think $16 shipping). I've had it two year and we put one in my dads pickup both run great /forums/images/graemlins/waytogo.gif
     
  5. gm4x

    gm4x 1/2 ton status

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    Summit PWM-8007 Powermaster, 70 amps @ idle, 100 amp, 1-wire. This one has screened vent holes, to keep out dirt & rocks. $150 .....just an option /forums/images/graemlins/thumb.gif
     
  6. ColAdo82K5

    ColAdo82K5 1/2 ton status

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    86 camaro 5.0 with FI....94 amp alternator. You might have to change the pulley, but they should do it for you at autozone.
    Blake
     
  7. bablazer73

    bablazer73 1/2 ton status

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  8. TopOff

    TopOff 1/2 ton status

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    SWEET!

    How does one find that alternator??? Advanced Auto isn't aroud me.

    I did find some 108 amp alternators but the best price I found is $94.00
     
  9. Z3PR

    Z3PR Banned

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    I've said this befor, and I'll say it again. Take your alternator to a local alternator/starter rebuild shop and have them build a hi-amp unit for you. Much cheaper then buying one from a parts house, and if you have any problem with it just go back to the shop that builds it for you. /forums/images/graemlins/deal.gif
     
  10. TopOff

    TopOff 1/2 ton status

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    Heh, not around here it's not cheaper to have an alternator shop build me an alternator.

    One alternator shop said he could build me a 100 amp unit for $100.

    Another shop said he could build me a 130 amp unit for ~$130.

    Yet another alternator shop said he suggests a 180 amp unit from a Ford for about $300!

    This KALI-forn-IA. /forums/images/graemlins/ignore.gif

    /forums/images/graemlins/1zhelp.gif
     
  11. Z3PR

    Z3PR Banned

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    [ QUOTE ]
    Heh, not around here it's not cheaper to have an alternator shop build me an alternator.

    One alternator shop said he could build me a 100 amp unit for $100.

    Another shop said he could build me a 130 amp unit for ~$130.

    Yet another alternator shop said he suggests a 180 amp unit from a Ford for about $300!

    This KALI-forn-IA. /forums/images/graemlins/ignore.gif

    /forums/images/graemlins/1zhelp.gif

    [/ QUOTE ] Ouch, thats outragous !!! It's so easy to build up. Bigger stater, and rotor combo and you're good to go. Damn, the shops out there are sticking it to ya.
     
  12. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

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    Same here, it costs more to have an old alt pumped up than just buying a new one from another vehicle. I Got a rebuilt alt. from a commercial GM truck. It is around 100-125 amps or something stock ( no expensive aftermarket parts)and is a large case instead of the small case alts that are stock on our K5's. The large case unit can handle running at full load for a lot longer than the small case because it despenses heat much better. It is basically bolt in, just bend your bracket back 1/2" and it should line up. Sorry that I don't have a vehicle/model/year for you and understand how frustrating it is but you could start with asking for an alt for a "P" series commercial van. /forums/images/graemlins/thinking.gif Or do what I did and go to a shop that rebuilds them on a regular basis and just ask for a large case GM alt., they should know what your talking about. /forums/images/graemlins/thumb.gif
     
  13. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

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    late 80's Subs have 105 ampers. Have to change the pully but that's no big deal. I just ran mine to FL, running lights, Dual A/C pulling a trailer so the trailer running lights as well, Stereo on, Bunch of junk plugged into the 3 way splitter for the Cig lighter....never droped below 13V. I'm sure I was running some low speed that got the AUX cooling fan to fire up. Never noticed the drop.

    I am also fairly well done with the chain rebuilds. I had the local shop rebuild this ALternator for $60. It had a cracked insulator that they missed. The PO fried it with a pressure washer. Guy worked with me on it and got it right. Showed me the part and didn't have a noticable problem till the retaining bolt pushed on it. then it opened up and shorted.

    The Customer service I got I have no complaints that they missed it. I would have missed for sure!
    He put it on his tester and it was doing 70 amps at idle speeds. he ran it up to about 1500 RPM and put 100amp load on it for 10 minutes. It never wavered.
     
  14. bablazer73

    bablazer73 1/2 ton status

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    Those part #'s are "generic" Any parts store should be able to cross over to theirs.
    Watch out using the ford alternaters. I think the one they sell with 180 amp is also not regulated. A seperate regulater IS required for another 100.00!!! Thats the one the on board welding kits suggest. But the one i got is approved to be used with on board welders. /forums/images/graemlins/waytogo.gif /forums/images/graemlins/waytogo.gif
     
  15. CyberSniper

    CyberSniper 1/2 ton status Premium Member

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    Just go to your local friendly auto parts store and make them look through the computer for the cheapest alternator they've got.

    I got a limited warranty remanufactured 70 amp 12SI alternator from Advance Auto for $34 plus core. It came with a spec sheet that gave the output curve. It peaked at something like 78 amps. It had like 80% of peak power by 1900 rotor rpm (which is less than what my truck idles at). It even came with mounting hardware and a new pulley.

    I ran it all day Saturday at idle with the electric fans on and ran the winch briefly twice. I have a 30 amp isolator. By the time I drove it home the half hour or so it was recharged.

    I haven't found a stock 12SI alternator that is rated for more power for under $70. I'm planning on eventually converting to CS144.
     
  16. 84_Chevy_K10

    84_Chevy_K10 Banned

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    A stock alternator for a mid 80s truck with A/C is 78 amps.
     
  17. R72K5

    R72K5 Banned

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    yes but std equipment alt was less than 78,

    and was 42 amp in 67-72 years i know


    cant believe shop wants so much to upgrade an alternator around here, we only have one tiny electric motor shop here and its only 30 bucks to completely rebuild a GM large alternator with all new parts and i know he could upgrade the output for not much more

    maybe i can start a small business out of this /forums/images/graemlins/thinking.gif hmmmm..
     
  18. mccomas

    mccomas 1/2 ton status

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    can stock wiring handle these high amp alternators? to go from 60 or so amps to 140 is quite an increase in amp flow… what wiring (if any) requires upgrade to a lower awg? or is this just not an issue?
     
  19. HarryH3

    HarryH3 1 ton status Author

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    The main output wire from the back of the alternator has to be upgraded. On most of our rigs this wire runs from the alternator down to where the battery cable connects to the starter.
     
  20. HarryH3

    HarryH3 1 ton status Author

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    Check out www.alternatorparts.com They sell parts to upgrade various alternators and also sell ready-to-run hi output alternators. /forums/images/graemlins/cool.gif
     

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