A couple of weeks ago, the bolts that hold the alternator on my '98 4.6L broke and the alternator fell off. I replaced the bolts and put the alternator back on. I was hooking the wire back on to the alternator, and stupid me did not unhook the battery, when my wrench connected with a metal bracket. After all was hooked up, I cranked the truck but the alternator was not charging. I used a meter and found no charge coming from the alternator. I replaced the alternator only to find that I am still not getting a charge from the alternator. I am getting 12 volts from the battery with the truck not running. I also only get 12 volts from the battery with the truck running. As you can tell I am no mechanic. Any advice?

 

You sure you have it hooked up right ?

heres a pic from an 2001 - The one below is a 98 , I don't have a good pic of that.

 

if you shorted it out with your wrench chances are you blew a fusable link.

 

What and where is the fusible link? Is that the primary battery fuse?

 

no its a piece of meltable wire comming directly off of the alternator. to test them just give it a light tug and if it stretches then its blown

 

I will check that, thanks!

 

ur alt is toast. the ones now days are not like the old ones they have some material forgot wat it was but its like silicone or something inside if u have the battery hooked up when installed they will fry them. we install them at work and everyone that has ever been hooked up with a bat still connected they fry

 

It's likely you killed the diodes. They can be reverse biased, but not at the current that you may have sent through if it was shorted. If I read it right, you replaced the alt. Does that mean you bought a replacement? If so, you should be getting 14+Vdc at the batty. when running. If not, just like the previous post said, check the fusible link. It's probably open. Just as an FYI.... silicon ( essentially, glass) is the substrate material for diodes for the rectification to a DC charge. Silicone is a sealant.