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Battery corrosion covering relays!? What Gives?

Discussion in '2nd Gen 4Runners (1990-1995)' started by Yoda69, Dec 22, 2023.

  1. Dec 22, 2023 at 8:08 AM
    #1
    Yoda69

    Yoda69 [OP] New Member

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    Good morning! Long Time Gen3’er recently picked up a 95 “project” as a lil treat for my 18 year old daughter who deserves way more than I could ever give her… so a tight lil gen 2 with 130k miles will have to do.
    As Dave Chappell says… “We aint poor, we’re just broke!”
    I picked it up for $1k and Im about to do my thing and earn some Mad Dad points .
    So Im coming to the “OnlySource of Truth”
    (Thats You Guys!!”)
    The only issue the guy had with it… that he is willing to fess up about up front is there has been an ignition short somewhere up under the steering column. He fixed it once before with probably some duct tape and bailing wire and it worked for him for the past 1000 miles. It went out on him again last week and he is not a wrencher at all and needs it gone. Im game so I talked him down from $4k to $1k and Im confident in yours and my abilities combined that we will certainly impress the Lady!

    My first bit of advice is if anyone can relate to or point me in the right direction regarding what appears to me to be an exploded battery that has covered the Passanger side engine bay including the relay box with what i can only describe as battery fluid that has dried and has covered everything with corrosion. Is that a thing? Common or a 1off? seems to me to be an obvious place to begin looking for the starting problem. Lmk what ya know? Ill be a forever “pay it forward” kinda member! Thx in advance! Ma name is Yoda69!
     
  2. Dec 22, 2023 at 12:03 PM
    #2
    negusm

    negusm New Member

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    I've found that battery corrosion that continues to get worse is always due to bad connections. For example, my neg battery post was getting pretty bad no matter how much I cleaned it and put gunk on it, it would keep corroding and actually wore the battery out early. I found that the terminal connector and about 8" of the wire was corroded inside the cable. I hacked it off, spliced in a negative cable and terminal with a torch, a ton of solder and flux and I have no visible corrosion for a few years now.

    Point is, look for bad battery connections, especially grounds. Don't just look at the ends, look along the wires and if they "crinkle" when you bend them, the copper inside is corroded and corrosion = resistance which is bad.

    Hope that helps.
     
    2Toys likes this.
  3. Dec 22, 2023 at 12:12 PM
    #3
    Yoda69

    Yoda69 [OP] New Member

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    Word! Thats the kind of Forum participation that is a rare thing these days! Thx for actually engaging with your input! I will in fact perform invasive surgery on all my major power draw components. I used to dabble in putting in high end car audio systems in my vehicles and you are correct! That corrosion can travel major distances just underneath the wire sheath. Thx again for the reminder!
     
  4. Dec 22, 2023 at 5:37 PM
    #4
    2Toys

    2Toys Imperial Star Cruiser

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    This! ^
    The other thing to look for especially in the big positive and negative cables is swelling. As the corrosion travels down the cable, the insulator will swell as the corrosion does its dirty work. If you have time, disconnect all grounds in the engine compartment and clean them, maybe with scotch brite and solvent. By the time you work your way through all of them, you will have some confidence.
     
  5. Dec 22, 2023 at 5:46 PM
    #5
    SlvrSlug

    SlvrSlug Slightly bent.

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    I used to use welding cable with some good connectors, you can get the length you need with a lot less work and cost is not that bad.
     
  6. Dec 22, 2023 at 5:53 PM
    #6
    negusm

    negusm New Member

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    One more thing...

    On the third gens, TOYOTA used inferior steel battery terminal connectors. On my repair, I went with the old school lead terminal connector. Dunno on 2nd gen.
     
    SlvrSlug likes this.
  7. Dec 23, 2023 at 12:26 PM
    #7
    AuSeeker

    AuSeeker Old As Dirt

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    To neutralize battery acid/fluid, mix some baking soda with water, about 1/4 cup of baking soda to 8 to 12 ounces of water, mix well (the baking soda will not dissolve so keep agitating the mixture so the soda is suspended in the water) and then pour/dip/flush anywhere that has the old battery acid with the mixture, rinse and repeat until there no more fizzing, using wire brush as you go along will help break up the corrosion so the baking soda can do it's thing, end up rinsing with fresh water after you get no more fizzing, then coat with a good corrosion preventative.
     
  8. Dec 23, 2023 at 5:41 PM
    #8
    SlvrSlug

    SlvrSlug Slightly bent.

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    This is fine if the corrosion is only at the terminals, but older vehicles have sometimes gotten corrosion deep into the cables.
     
  9. Dec 23, 2023 at 6:54 PM
    #9
    AuSeeker

    AuSeeker Old As Dirt

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    The info I posted wasn't meant to fix damaged cables or even corrosion, it was for neutralizing battery acid the OP says was sprayed/splattered in and around the engine compartment.
     

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