Alternater problem 6.9 Diesel

[Hearsedriver1963]

Truck been ok untill yesterday went to get tires installed and Batteries dead when i arrived at tire place (amp guage non operational)charged it up while fixing tires,took home and figured needed new belt as it was getting thin and kinda loose, While changing belt wrench from bolt on alt. touched inner fender throwing sparks,I dont believe there should be power to outside of case,cant find any shorts ,going back out and keep looking.. Any suggestions would be really appreciated,Thanks

[BPofMD]

Have you tried to post this problem up in the 6.9 diesel forum? You might get a quicker response.

[Franklin2]

Do you have a meter? Get it running, and measure the battery voltage. You should have around 13.8 to 14.5 volts if the alternator is charging.

If you can get sparks from the case to the metal of the truck, then the alternator has become ungrounded. I had this happen on a 7.3 diesel, but it was a very rusty truck. I ran a large #10 wire from a stud on the alternator case, over and hooked to directly to the battery negative clamp bolt, and it took care of it. It was so rusty, there was no way I was going to try and take the alternator off and clean up the mounting points. They had already broken the long bolt underneath.

[Hearsedriver1963]

Thanks for the reply,had no engine ground,and a light under dash was stuck on,2 wires melted together..