charging problems

[Raynmanvb]

Hey yall whats up. So im having a problem figuering out a charging problem with my 97 f350 it all started when my battery gauge droped and my battery light came on so i figuered its a bad alternator no problem i can handel this so i took off the old alternator wich had bad bearings and went to the local store and picked up a alternator and installed it. i let the truck run for a while and it did not charge so i went back to the local store and had them test the alternator and the batterys guy said thier fine but i figured something was wrong with the alternator anyway so i decied to take it off and take it back now when i went do this the alternator was so hot that when i touched it it burnd so i poured water on it and took it off took it back to the store handed it to the guy behind the counter and he says oh my god this things hot and noticed you could barley even turn it and gave me a knew one so i put the new alternator on and now if the truck is at idle the battery gauge drops but if i rev it to 1000 rpm or above the battery gauge goes back up to normal but now the battery light does not come on any more so i went and bought two new batterys installed them and the truck is doing the same thing so i just really dont know what to do could it be the alternator new batterys or just some kind of wiring issue well i dont know maybe one of you guys have had a problem like this sorry for the long story but i figured yall should know. thank you in advance.

Raynmanvb

[gbear]

Most of the time new batteries should be charged with regulay battery charger. New batteries can fry a good alternator. Alternators are
built to mantain the charge. It seems like the newer ones (from the 90's forward) aren't built as strong as the older ones.

[mschn99]

sounds to me like another bad altenator. make sure the wires to the voltage regulator and stator are secure and making good contact at the pins. also, if you have a good ohm meter, disconnect the cables and check the resistance of the wires. you could have a high amp draw from the starter but that generally wont cause a gauge problem, so we can probably rule that out.

What i would do first is check the altenator output. Get an voltmeter, and see what the altenator is putting out. measure from the positive post ON THE ALTENATOR to ground. it should be roughly 14 volts, give or take a little.

if this is low, the altenator is bad. if it is normal, it is a wiring problem more than likly......

[Raynmanvb]

Hello every one. well i charged the batterys this morning and the gauge is still doing the same thing but i did get the chance to install a new boost gauge so i guess i will change out the alternator tomorow i will let yall know what happens.


Raynmanvb

[z250kid]

i have a 1996 F350 4x4 powestroke
im having a simlar problem
i replaced the battieries and had the altenator checked they said it was good.at idle it doesnt put out 14 stays at 12 and when its about 1000rpm it puts out some voltage but when its about 1500 its about 14ish. i dont know if its the altenator or regulator i need to find out before winter.
any help is appriciated

[DneprDave]

I have a '97 F-350 also. When I got it, it had a new alternator and one new battery. It would not start every few days because of a low charge. The volt meter was reading too low to be charging the batteries. I cleaned up the battery terminals and battery connectors on both batteries, it has worked fine since.

Dave