How to rebuild an alternator of a ford f250 - 1988 Ford F 250

I would reccomend you go back to the alternators again. Have it tested. There are many bad parts going over the counter these days, and I have replaced"new alternators" 3 times before getting a good one.

There is a 10amp fuse for the gauges and the circuit that turns on the alternator. I think the fuse is in the engine compartment fuse box but your owners manual would tell you for sure.
You need to know if that circuit has power with the key switch on.
The wire going from the fuse to the instrument cluster is red and yellow and the wire between the cluster and the alternator is lite green and red.

maybe a bad ground somewhere

Below is a link to the wiring diagram on a F-250 with 5.0L (302ci). Best of luck.
Greg

Wiring Diagram Schematic 1987 F-250

Does the battery charge even after it drains. Even though it's a new alternator, it could still be bad. The battery could even have a dead cell because it's draining while you're driving. Sounds mainly like the alternator output isn't enough. Internal voltage regulator inside the alternator is usually a big problem, it can't be replaced, except by a new alternator or have yous rebuilt.

Bad connection or maybe bad cell in battery.

Thats a guessing game, but first, if the battery light was on, that means no alternator output. So recharge the batteries and be sure they are good, Then replace the alternator. If the batteries and the alt are good, and the battery light is off, then all should be OK.

Rebuilding an automatic transmission requires more than looking at a diagram. Check out faxonautoliterature. They have the original Ford service manual for your truck and it will have all the information that you will need to rebuild your trans properly. Hope this helps.

has anyone thought about the regulator, i think that its built into the alt, replace it and then see if the prob continues, you can get a pass on the alt test and still have a bunk regulator

when you replace a alternator make sure battery is fully charged 1275 hydrometer reading on all cells. alternators will get hot. if you purchased from a cheap auto parts store with the lifetime warranty youll find out you purchased a life time of changing substandard parts (and they only replace 3 times)i would suggest you take it to a local rebuilder (whole vechicle) and have tested