not staying charged

[longhorn795]

okay so I just bought a 1998 12 valve and it is not staying charged, it was a 24 valve and they done a swap and put a 12 valve in it, the batteries will charge up but after driving for 20 minutes the volt gauge will go to 0 and nothing electrical work's, put a new alternator on it and still the same thing and ideas? thanks

 

[argve]

Check the fuse on the drivers side under hood electrical box. I replaced an alt for not charging only to find that there is a fuse between the alt and the batteries. If I remember correctly it's something like a 80 amp or such. It actually bolts into place. I ended up just jumpering it out to get from the campground to the autoparts store one afternoon.

 

[Armo]

This isnt vehicle specific advice but i had someone disconnect a voltage regulator on a different vehicle that exhibited a similar thing would show a charge then drop to 0 and drain the battery quick. Since it was a swap thought id toss that info out their.

 

[058hammer]

Could be the regulator built into the ecu. You can put an older style one on.