7.3 idi charging

[ericwade381]

Hi everyone I'm new here I have a 88 f350 and when I bought it the guy said it would drain the batteries. So I have new batteries a starter replaced the alternator and the voltage regulator. New injectors and glow plugs. I went to start it and she did start after putting the new alt today switched to my rear tank after fixing my sending unit and she turned off. Now after charging the batteries for a few hours I get one good crank session and after the the batteries are shot?? Do I need to charge the batteries long? The way they have wires cut and just everywhere would make an electrician scream

 

[C_Luft]

To charge the batteries full or enough to start in the morning you need to take her for a drive, for about 15 min, maybe longer since you have two batteries. I'm no electrician but I hate bad wiring, when I got my truck from the previous owner I had your same issue with batteries draining, he had all sorts of crap wired to this truck 4 front fog lights, 2 rear fog/work lights, and some other junk plug in crap, I ripped it all out and let's just say I had enough wiring for some of my friends to use and still have a lot left over.

My suggestion for the batteries draining would be to go through your wiring and make sure your contacts are good and tight. In my opinion I would pull out the aftermarket wiring and start from scratch, unless you know where everything goes then just repair it

 

[FARMFUEL]

Disconnect both ground cables from the battery. Make sure everything in the truck is turned off, like the stereo. Doors closed. Lightbulb removed from the hood. Now take a test light, with a known good bulb inside, and hook the ground clamp to the ground post of the battery. Put the needle in the ground cable terminal. If the light lights up, you have a current drain. Start pulling fuses until the light goes out. Fuel problem isn't related. Once you open the door, or turn the ignition on, the light bulb inside the test light will get real bright. Remember that you don't have the batteries connected. Pull the fuse for the interior lights. Some circuits aren't fused, and have fuseable links. Especially over by the alternator.

If you pull all the fuses, and you can't isolate the parasitic drain, start disconnecting components, like the regulator, or the alternator. There is a diode inside the alternator, that acts like a one way current valve, not allowing the alternator to drain the battery. It takes power to make power, and if this diode is bad, the alt will kill the batteries. Doesn't matter if its new, rebuilt, etc- it came from Bangladesh, and it's not to be trusted!

 

[sassyrel]

alt's can go bad many ways...the brushes cab be totally gone, grooves waaay deep in the slip rings..then, the diodes can go bad three ways. they can short to grd, go open,, or go reverse!!! that's why when you shut it off, the batteries drain....disconnect the hot wire off the back of the alt, with the batts charged up...next morning, if the batts are still up,,bad alt.. be it new, rebuilt , or used!!!!!

 

[laserjock]

I have a subaru that eats alternators about every year. Always some internal failure that drains the battery. Is your alternator warm at all after its sat for a while?
FARMFUEL gave a pretty good regimine for finding a draw, but I'm with sassyrel, start with the easy thing to check first. You say you replaced the starter right? How are the cables? They can cause it to take more juice to crank than necessary. Could have got a lemon starter too depending on where you got it.

Good luck.

 

[ericwade381]

Hey guys thanks for the help I did however replace the alternator and charge the batteries up and let the truck run for a good while. Seems like it is holding a charge so far and cranks right up when I go to start at. I'll keep my fingers crossed hope way it was just the old alternator that needed to be replaced. Also do you guys know if there is an app that you can get on your phone for this site

 

[ericwade381]

The guys before me remove I mean everything electric stero interior lights horn hood light gone??!!

 

[snicklas]

...Also do you guys know if there is an app that you can get on your phone for this site

Yes. Tapatalk works on this site. Take a look on your "flavor" app store. Not sure how to use it, as I have a dumb phone and a real PC that I use. Many on here post with Tapatalk.

 

[79jasper]

When you open the site on your phone, it should prompt and ask if you want to download Tapatalk.

Sent from my SM-T537R4 using Tapatalk