What’s everyone using to fuse between the alternator and starter relay

Discussion in 'Electrical and Ignition' started by Barnes, Jun 10, 2018.

  1. Barnes

    Barnes Member

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    I did the ammeter bypass on my 68 and currently have 6 gauge wire from the 60 amp alternator, to a 80 amp circuit breaker, then to the starter relay. My problem is the circuit breaker is tripping on hot days (I believe the breaker is faulty, tested with another alternator). I would like to try another way of fusing the charge wire and would like to know your ideas. Fuseable link, another brand circuit breaker, mega fuse, none?

    Thanks!
     
  2. 67Dart273

    67Dart273 Well-Known Member

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    1...How large is the alternator (output rating?)

    2...WHERE is the breaker mounted? Engine heat will de-rate the trip amperage
     
  3. Barnes

    Barnes Member

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    The alternator is a 60 amp square back and the breaker is mounted next to the battery, in the engine bay.
     
  4. 512Stroker

    512Stroker We are all here because we are not all there.

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    I have a 60 amp alternator and a 70 amp CB mounted next to the battery, has never tripped.
    Even with the factory A/C on.
     
  5. Barnes

    Barnes Member

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    What brand CB are you running?
     
  6. 512Stroker

    512Stroker We are all here because we are not all there.

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    Dont let the name foul ya, got it at Oreily's

    Littlefuse 0185070.X Type lll 70A
     
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    • Barnes

      Barnes Member

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      Awesome, thank you.
       
    • 67Dart273

      67Dart273 Well-Known Member

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      It IS possible you have a weak / faulty breaker.
       
    • swifty

      swifty Well-Known Member

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      Make sure connections are tight and clean. Look for signs of heat from high current. A bad crimp or connection can draw a lot of current.
       
    • billccm

      billccm Well-Known Member

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    • Barnes

      Barnes Member

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      Update: I have been using the breaker 512Stoker recommended. So far so good. Has not tripped once. I must have had a bad/cheap breaker. Thanks again for the help.
       
    • 512Stroker

      512Stroker We are all here because we are not all there.

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      Every once in awhile a blind Hog finds an acorn. LOL
      Glad it work out for ya
       
    • rednesss

      rednesss FABO Gold Member FABO Gold Member

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      Why run a breaker at all?? The fusible link was to protect all the wiring under the dash, bypass that, and there's really no need on the run from the alternator to battery post/starter sol. Just make sure and size the wire right.
       
    • 67Dart273

      67Dart273 Well-Known Member

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      "I have news".............a story from the old days

      "Back in the day", not long after buying my 440-6 RR from a friend (who I saw last summer) some girls were "window shopping" in National City S of San Diego and REALLY A-holed it. Not knowing better, McCune Chrysler Plymouth got it "to fix" and I got a junk loaner car, Valiant /6 with bald tires and rock hard heater hoses. One of them broke, later.................

      ANYWAY my Chief PO came in one morning and it was "cool" out. I had fired up the thing about 5 min. earlier and was in the shop, getting "off duty." He gave me the "Columbo" bit and says "is that supposed to be screeching and smoking?

      SO I went out and shut it off, THE ALTERNATOR WAS NOT ROTATING. I took a rag and wrench and investigated, when I moved the pulley, THE DIODE THAT HAD FALLEN DOWN INSIDE SHORTED

      I got to sit there and watch THE ENTIRE ENGINE HARNESS go pppppsppsppsssssshhhhhssssppphhhhtttttt...........ssssssssss........ttt!!!

      AND THEN THE FUSE LINK BLEW


      So it shorted and melted the underhood harness into a huge stinking mess AND THEN popped the fuse!!!

      Called the dealer and told them to send a tow truck and a different loaner car. They sent the wetback with the booster cables instead. I went out and he looked at me and said "YOU NEED A TOW TRUCK!!!"
      This old photo is from either '73 or 74
      81sruds.jpg