Electrical issue

Discussion in 'Troubleshooting & Diagnosis' started by Dennis Wilkie, Jun 15, 2021.

  1. Dennis Wilkie

    Dennis Wilkie Veteran Member

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    I just finished up a tbi to carb swap on a sbc 350 and I can't figure out what's going on with it. I got it to start up last night, but today all it does is make this noise, and it acts like there's a short or something, but I can't find it. I don't know if it's the starter or what.
     
  2. Jim Streib

    Jim Streib https://www.flickr.com/photos/[email protected]/albums

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    Do you have the cheap 99 cent battery terminals on the car ?.

    [​IMG]

    I got caught troubleshooting a car at a cruise recently that had these buried under tape and the bolts had become loose that clamped onto the main starter cable that ran down to the starter but the guy had a ring terminal for the wire that went to the rest of the car going to one of the bolts that kept a good connection. It would clunk like it was going to turn over the motor but the motor did not crank over at all. He just had the solenoid clunking or engaging but without main power on the large cable getting to the starter it would not crank over.

    Maybe too the starter needs to be shimmed and the starter gear is not getting into the flywheel teeth properly ?.

    Also too, turn on the dome light or headlights and try cranking it over.If the domelight or headlights go off, then look at your connections.

    Maybe too go over all of your connections. It might not have been anything related to your prior work but things happen out of the blue sometimes.

    Jim
     
  3. biker

    biker Veteran Member

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    That sound is your starter solenoid throwing the bendix drive out to engage the flywheel, but no power is making it to the starter armature. Likely a dead spot on the starter. Crawl under and give it a smack with a hammer while someone cranks the key.
     
  4. biker

    biker Veteran Member

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    Or you can reach it from the top with a broom handle. A whack or 2 might get it to turn over, but the solution is a new starter.
     
  5. Dennis Wilkie

    Dennis Wilkie Veteran Member

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    I agree. That was pretty much the same conclusion I came to earlier. I've been waiting on the sun to go down to go back out there, but I plan on getting some definite answers shortly. But i've got good terminals. I think they were like $30 for the pair. I put a test light on it looking for a short last night and when I pulled the radio fuse, the light went off and I started it right up. Tried it without the fuse again today, and got that noise. Same noise it was making before I got it to start.
     
  6. biker

    biker Veteran Member

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    Yeah, when the bendix flings out, it makes contact with a big lug that supplies high amp 12v to the starter motor. If the starter motor doesnt turn, it's on its way out or already dead.
     
  7. McCune

    McCune Veteran Member

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    I can hear the bad connection sizzle on the last three clicks. Hitting it with a hammer wont do anything with the way the starter is acting. A open or dead spot as people call it will never click like that!
     
  8. Dennis Wilkie

    Dennis Wilkie Veteran Member

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    I just went through all of the wiring I ran when I did the swap, and I couldn't find anything wrong. But the starter is definitely not the problem. I jumped the posts with the key on and it acted exactly the same. But I took it off while I was doing all of this and for the life of me, I can't figure out what's causing this. It's 100% an electrical problem somewhere. I can feel a current through the body when it tighten the positive side, but can't find a short anywhere. But I had nothing connected to the positive side of the battery while I was doing this, and was getting a voltage reading off the front cap when I tapped the positive terminal. https://youtube.com/shorts/4B3ANx0R-Fw?feature=share
     
  9. Dennis Wilkie

    Dennis Wilkie Veteran Member

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    That was the hot water I poured on the posts to clean them off
     
  10. biker

    biker Veteran Member

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    Jumping the terminals on the solenoid wont spin a dead starter. It just bypasses the solenoid. Did you bench test the starter while you had it off?
     

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