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updating wiring question

Discussion in 'Retro-Fit & Aftermarket Accessories' started by spanky55amg, Jan 8, 2019.

  1. spanky55amg

    spanky55amg I'll give u $5, a hardy handshake, & 5 fish sticks

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    Ok. So I am cleaning up the wiring with the engine and transmission R&R and taking away some of shotty audio cable that was used.

    I read the big 3. The shotty audio wiring from the PO did do some of that. I read at least 4ga wiring at least.

    1. Would 4 ga welding cord be sufficient? Have you messed with welding core? Is 2 ga pliable? That shit adds up quickly.

    2. The shotty wiring included a ground from the Alt. bracket to the battery. Is the Alt. case or bracket the best for the engine ground? (The vehicle has 0 other grounds from the engine.)

    3. Should there be a ground from the firewall to the chassis?

    4. The engine is a TBI engine, so the alternator is being relocated from the passenger side to the drivers. Should I go bigger than 12 ga from the alternator to the starter? Say something like 10 or 8 ga?

    5. Same thing about from the starter to the junction block, should it also be bigger?

    6. From the alternator to the junction block, stock is 12 ga. Once again, should it be bigger, like 8 ga. I had a buddy even suggest 4 gauge to the junction block.

    7. Any other suggestions? Yes there is audio equipment in the truck.

    ***NOTE, I know the wiring diag has the wiring in metric. I changed it to AWG.***
     
  2. Matt69olds

    Matt69olds Full Access Member

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    I would think 8 gauge would be good to about 75-80 amps of alternator output. If your alternator is capable of more current then step up the cable size. As far as alternator case grounding, assuming there is no paint or crud insulating the alternator, there should be no need for a ground wire. And a ground wire from the engine to the firewall is always a good idea, as is a heavy ground wire from the negative battery cable to the core support.
     
  3. spanky55amg

    spanky55amg I'll give u $5, a hardy handshake, & 5 fish sticks

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    Yeah. I’m going from a 10SI to a CS130. I don’t know what amps the 10SI is but the CS130 is 105.
     
  4. Blue Ox

    Blue Ox Turning Diesel Fuel Into Fun

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    There are tables and calculators for 12V DC wiring based on amperage, cable run and allowable voltage drop. You'd need to measure the run from the alt to the starter. We're going to @$$ume the block is grounded via the battery cable, so we can consider that the total run, but in most situations you need to measure both the positive and negative length for a DC circuit.

    For example a 10 ft total length 100A 12V circuit at 3% calls for 2ga.
     
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  5. spanky55amg

    spanky55amg I'll give u $5, a hardy handshake, & 5 fish sticks

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    I’m going to find this. Thanks!
     
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  6. Blue Ox

    Blue Ox Turning Diesel Fuel Into Fun

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    I don't have this stuff in front of me, but if you need, I'll post links to calculators when I get back to work on Monday.
     
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  7. Blue Ox

    Blue Ox Turning Diesel Fuel Into Fun

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  8. spanky55amg

    spanky55amg I'll give u $5, a hardy handshake, & 5 fish sticks

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    Thanks .I also looked around .I found one fusable link dead. As soon as I disconnected it from the junction block, it disengrated in my fingers. It burned through the sheathing. So I don't know how the truck was even running.

    Question .do I need the metal eyelet that goes between both post of the junction block and is connected to the fusable link?
     

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