engine not cranking over?

1984 CHEVROLET VAN
63,000 MILES • 7.4L • V8 • 2WD • AUTOMATIC
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STEVEN GRIBBINS
  • MEMBER
  • 26 POSTS
I bought a new Alternator because my battery wouldn't charge, so I bought a new isolator because it wouldn't charge the battery. it started just fine until I changed isolator now it will only start if I Jump large post of isolator to ground on Alternator bracket where I have isolator bolted to.
Feb 11, 2024 at 8:31 PM
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STRAILER
  • ✓Experienced Mechanic
  • 55,238 POSTS
I don't know how the isolator is wired but here are the wiring diagrams for the alternator and starter, I would go back to basics and make sure the connections are correct. Here is a guide that may help as well, and I have included the wiring diagrams for the starter and alternator systems, one of them is a little hard to read but it is all they are giving us.

https://www.2carpros.com/articles/starter-not-working-repair

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Feb 12, 2024 at 1:39 AM
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