OT, I know, but you guys know stuff

This is wildly off-topic for RAMJ+W and my abject apologies are offered. My address above is valid if you prefer to reply off-group. I'm only asking here because you guys know your stuff, I trust you and I don't do this very often.

I'm helping a friend with his motorhome, which was built on a 1990 GMC chassis with a big-ass V8. I know that it had a reverse-polarity episode with a completely dead battery and some poorly-designed jumper cables (black cable ends in red clips, yellow cable ends in black clips, a mistake just waiting to happen). A new battery later it cranks but does not start. I haven't seen it in person yet.

I'm guessing that the reverse voltage took out the ignition computer, would this be likely? I plan to meter the coil primary side and look for voltage and pulsing during cranking to be sure. Anything else likely to have let out a little Magic Smoke, like alternator diodes or voltage regulator? I'm hoping to prevent cascading failures once I get it started.

Thanks in advance,

Lee

Reply to
Lee Ayrton
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My bubba did this to a '86 Toyota PU I gave him... took out the big

40A fuse and the ignition module. $50 at the junkyard for a used module and it runs again... if you're dealing with injection, the computer for that probably smoked too. __ Steve .
Reply to
Stephen Cowell

Very likely he took out the fusible links at the starter solenoid. These are 8" long soft rubber wires that connect to the harness with big fat crimp connectors.

You can buy the wire in bulk either by the color or gauge and the replacement needs to be crimped in. They are typically 2 gauges smaller than the circuit they protect. If the ignition circuit is 10 ga., the link is 14 ga.

This happens in Jeeps as well if someone boosts wrong.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Lee Ayrt>

Reply to
Mike Romain

Reply to
L.W.( ßill ) Hughes III

Hmmm, I just downloaded a 5+ MB file to see 31 seconds of your family vacation pictures?

I've got to work on the Jeep more and surf this newsgroup less.

Reply to
matthewf_boi

Reply to
L.W.( ßill ) Hughes III

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