is it safe to run a 150amp alt with no 4ga wire?

Discussion in 'Fox 5.0 Mustang Tech' started by sidewayzisbest, Dec 20, 2003.


  1. sidewayzisbest

    sidewayzisbest New Member

    Joined:
    Feb 6, 2003
    Messages:
    430
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Lexington, SC
    Well i got the fuselink(of coarse not on yet) and everything just no 4 gauge yet, i wont be driving but i just want to start it up havent started it in like 4months and yall know how that is.....thanks the only eletronic i have is a mark 8 fan
  2. 85 Coupe 5.0

    85 Coupe 5.0 Founding Member

    Joined:
    Dec 18, 2001
    Messages:
    815
    Likes Received:
    0
    Trophy Points:
    16
    Location:
    Kansas
    I'm not sure, but i have a 3rd 120 amp on mine and the old '85 wiring for the 40 amp got hot, so i re-did it with 4 ga. or so. It would probably be ok, just keep everything electrical off untill you get it done right. I only had a problem when I had my A/C on untill I changed the wiring.


    Sponsored Ad

  3. TIMMY2734

    TIMMY2734 Founding Member

    Joined:
    May 17, 2002
    Messages:
    1,332
    Likes Received:
    0
    Trophy Points:
    36
    Location:
    Queens, NY
    I guess you could since your not going to drive the car, but be very careful. The stock wiring cannot handle that much power.

    However if i were in your shoes, i would just wait the few days till you get th e4 guage. The car hasnt started in 4 months, whats another 4-5 days on top of that?
  4. speed1972

    speed1972 Founding Member

    Joined:
    Mar 14, 2002
    Messages:
    894
    Likes Received:
    0
    Trophy Points:
    16
    Location:
    Denver, CO - Buckley AFB
    if you're only going to be starting it for a few minutes, just make sure the alternator is disconnected. unplug it, it will run off the battery fine for quite a while... thats what I'd do until you get 4ga wire....Larry
  5. Michael Yount

    Michael Yount Advanced Member

    Joined:
    Apr 10, 2002
    Messages:
    9,047
    Likes Received:
    0
    Trophy Points:
    77
    Location:
    Charlotte, NC
    The alternator doesn't put out power by itself - it has to have power 'drawn' from it by accessories. So it won't put out 150A unless you have accessories pulling that much from it. As someone said, be sure as many accessories are off as you can - including that fan which pulls a bunch of amps. As long as you do that, you should be fine starting it up and even for short drives. Just watch your temps. But get the 4 gauge on it asap. If you have a mini-starter, you can simply run the 4 gauge down to the large gauge hot cable on the starter with your fusible link in between. Save you some cable. That approach will not work if you have the older style large single-wire starter; you'll have to run the alternator cable over to the battery or the hot side of the fender mounted starter switch.

Share This Page