low volt guage when running

[mad rad]

In short,my volt guage is reading 9 volts,but both batteries show 13-14 when checked with engine off,but when engine is running the right side battery shows 10-11 volts,the head lights are dimer than before.this happened once before on a road trip after I had the ac on for a while and this time I had the ac on for a while then it started going down (the guage)again,this time it hasn't recovered.I unplugged the ac and the volt cheks are the same.

[CleviteKid]

The first suggestion is to check all the major battery connections. If you have not yet done so, change out the original battery bolts for the improved battery connection scheme described in this link: BATTERY CONNECTIONS. (http://www.thedieselpage.com/members/batterm.htm)

Then undo, clean, and reconnect the grounds on the block, and the jumpers to the frame. Also redo the cable connections at the starter motor and at the alternator.

Since your batteries seem fully charged, your alternator is probably OK, and bad connections dropping voltage when there is an electrical load is the most likely explanation.

On my truck, I have dual terminal batteries, and I ran an extra positive cable between the positive top posts on both batteries for extra assurance that the electrons can get to where they are going by a low-resistance path.

Dr. Lee :cool:

[mad rad]

thanks,on my way to hardwhere store.

[mad rad]

removed and cleaned everything and works great,thanks.going to replace all battery leads with welding leads and change bolts this weekend.

[CleviteKid]

Mad Rad:

Glad to hear your troubles went away. That is one of the wonders of TheDieselPage.com, that here you get answers, and soon as you gain experience, you will be providing answers to other questions posed by other members.

Welcome aboard, and enjoy your diesel ! !

Dr. Lee :cool:

[mad rad]

Thanks,I've been reading for a while just havn't had any big problems yet,,,,I'm new to diesels and I should of fixed this myself,I just made the problem bigger than it was.Anyway,thanks to all and now that I have time to drive this truck more I'm sure you hear more from me.