New alternator not charging

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AncientSword

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Hey guys, my 18 year old son was doing a cam and lifter swap and the alternator seemed dead after he got everything back together. I was busy and told him to go have it tested at a store. They said it was bad and he ordered another one.
He put the new alternator in this morning and the thing still isn't charging. Thing is that I tested it's output directly with a multimeter and it's putting out 14.8 volts.
After talking it through, he remembers that he pinched his wire loom that runs down that side of the motor when he was putting the valve cover back on. I'm thinking he cut that wire sand it looks like it runs right to the alternator. It must not have pinched anything else in there because everything else seems fine, no codes and the truck is running good.
We took a jumper cable and ran it directly off the + cable to the battery and started it up to see if that made a difference. It was charging with that jumper cable connected just fine. My question is can we make up a short cable to run directly like that without damaging something else?
He needs to use the truck and doesn't have time to tear into the loom today. We don't want to risk damaging something else by doing that. Is it safe to do?
He's been carrying around a spare battery all week snd charging it nightly while waiting for the alternator to come in. He can keep doing that in the mean time if we need to.
 

ibike

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Isn’t the wire between the battery and alternator a fuseable link? If he pinched it then he probably shorted out the fuseable link and it need’s replaced. A straight wire will increase your chances of burning the truck to the ground.
 

pacofortacos

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Read the Big 3 upgrade.


I would remove/disconnect the old wire from the alt and battery - to prevent possible short - then just run a wire from the alt to the battery until you can pull the harness apart and check for more damage.
 

pacofortacos

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Your regulator is in the pcm, repair this correctly to avoid problems. You have located the issue , don’t band- aid it.
PCM wire is fine, hence the 14.8v at the alternator - it is the large alternator to battery wire that he pinched.
 

Dean2

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With the fuse in there should be fine till you get the replacement. Paco's advice to run the wire straight with no protection is a REALLY bad idea, you guys did it a bunch more safely.
 
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