Hello everyone, im new here but have been reading your posts for quite a while and got alot of good info. I have a 1992 f250 4x4, 5.8 5 speed manual. A few months back i blew the motor going up a steep hill and decidid to get a diesel truck and convert it. I bought a 1989 ford f350 diesel with a good motor and wrecked body. i did the swap and it came out awesome but the only problem i have is the batteries are boiling over cause its charging well over 17 volts and i i rewired it and changed the regulator and alternator. It idles at 14.5 and as soon as you hit the throttle it pegs out over 17 volts. Ive checked it over and over, i have all the grounds in place and added more. the engine is grounded to the frame and body in more places then before, the regulator is grounded to the body and frame. This has been driving me crazy. I hope someone can help..thanks

 

I'll be following this since I am having issues with my 89' F350.

 

How is the regulator wired? Did you take the wiring from the 89 with that charging system?

 

welcome to FTE.
are you using an external voltage regulator, or an alternator with built in regulator?
either way, your voltage regulator is not working.

 

Hey guys thanks for your help. The original 5.8 had the alternator with the internal regulator. the alternator im using with the diesel has the external regulator. the alternator with the internal regulator wont bolt up to the diesel. I took the wiring from the doner truck and installed it in my truck. I bought 2 external regulators and its still overcharging, so thats 3 regulators that i have tried so i dont think the regulator is bad. I dont know where to go from here. If i disconnect the regulator when the truck is running it stops charging. Checked the wiring again and everything is hooked up. Is it possible that the regulator is charging to much cause it doesnt see its charging? I dont know if the alt guage wiring is different with the internal regulator alternator or if it makes a difference. Sorry for all the questions i just need to drive my truck so i have to resolve this. thank you for all your help.

 

How/where is the external regulator mounted? It needs to be grounded through its mounting base / case. Check for continuity between the case of the regulator and a good ground (or the battery neg). Or just run a wire from one of the regulator mounting screws to a fender ground.

Just going from memory, but IIRC, your '92 truck may have plastic fender wells, where the regulator is mounted. The older trucks that had external regulators, the fender well was metal, and grounded to the truck body.

 

The regulator is mounted on the plastic inner fenderwell and i ran a ground from the mounting bolt to the battery ground and to the frame. There is no shortage of grounds on this truck. lol

 

If it's in the budget, either time for a junkyard set up or money for new parts, one of the best upgrades you can do is convert the truck to a newer style 3G setup.


https://www.ford-trucks.com/forums/1...lt-pulley.html

 

You need to give us pictures of everything. I'd be willing to walk you through re-wiring it correctly, but I need pictures(and you to care).
You can do a 3G upgrade and it will work, but if you use good wiring and a good regulator, the 1G works just fine. And is much cheaper, cause you have it.

 

I went to a diesel shop today that does high performance upgrades and tuning on ford super duties, chevys and dodge cummings and he said the computer in my truck has something to do with the overcharging. He said the regulator is not seeing that its charging so its overcharging. I dont need the computer anymore cause i pulled the 5.8 fuel injected motor out. The 7.3 dont need it so i disconnected it when i got home and its still overcharging. I would have to think there is a wire that has to be cut or grounded.I can send a pic of a diagram on how its wired now so you can see it. I cant get a wiring diagram for the charging system for the truck, all i was able to get was the wiring for the 1989 from ALL DATA. the green wire with the red stripe from the regulator goes to the amp guage but the wiring for the 92 is different. the took the dash apart and the 2 wires going to the amp guage are black with a white stripe and red with a yellow stripe. Im missing something thats right in front of my face and cant seem to find it. I hope all this makes sense.

 

I can go to U pick it and get a 3g alternator but dont you think i wouild have the same problem? If the regulator doesnt see that its charging wont the 3g alternator overcharge to? I would think it would do the same thing>

 

The 3g setup has an internal regulator, so it figures out how its charging by the output wire (or something like that). The problem you appear to have is the regulator you are using is improperly wired so its not working correctly.

The 3g is also wound better so can output more amps than the 1g alternator. That may not make a different for your situation.

For what its worth, the guy at the diesel shop probably doesn't have a clue how our older trucks actually work. Theres no computer in a 92 diesel either (unless is has the e40d) so it shouldn't be a computer problem at all. Sounds to me like you have something wired wrong and need to get us some pictures of where you spliced things together....

 

^^^ In addition, none of the diesels with a computer, whether an IDI with E4OD, or a PSD, have any connection between the computer and the charging system. As said, it's most likely a wiring problem, IOW an electromechanical (not electronic/digital) problem. Any mention of the computer indicates that mechanic is out of his field.

 

I vote 3g swap, great upgrade all the way around, more amps, more reliable, worth more effort. I picked mine up for $20 swapped pulleys spliced 3 wires added a real charge cable and done.

 

Our 1G system has just the alternator and regulator. That's all there is to the charging system.
the 3G just has the regulator inside the alternator unit, so it's a single part system; less wiring.