86 f250 help

[dv13]

I am new to this whole forum thing.

I recently got a 86 F250 for dirt cheep. The guy i purchased it from had swapped the 6.9 to a 1990 7.3 idi.
In doing so he messed up the glow plug harness and attempted to run the alternator w/ internal regulator off a toggle switch which there for screwed up the wiring harness and will not charge what can i do to fix this problem or find a wiring diagram because i can not find one anywere.
Any help at all will greatly be appreciated.
thanks.

 

[icanfixall]

Welcome to the forum. Not very good with electricals on these rigs but the answers to the 6.9 to 7.3 swap is not an issue. These engines are drilled and threaded exactly the same so any part on the engine will swap over. So the V belt drives could have been swapped and the engine would have worked fine. I did an external voltage regulator swap to an internal regulator swap years ago. Easy and cut just a few wires but I can't recall what wires. I did get a harness for the alternator with the internal voltage regulator from a wrecked truck too. It was a simple connect and run thing. I went from V belt to serpentine belt drive too. the V belt alternator had the external regulator...

 

[1466IH]

you should just need an exciter wire for the field then a large wire that runs to the batt. Depending on what alt was used some have a couple extra terminals one for a gauge and one for a tach cause some engines use the alt for the tach pickup. so just run a small jumper wire from pos batt terminal and hook it to the smaller terminals one at a time untill you get power out of the biggest terminal then run once you have figure out what terminal is need find a key on powersource and tie into that for the field wire and run a heavy wire from the biggest terminal on the starter to batt pos

 

[ToughOldFord]

A 90 will be V-belts unless it was converted. S-belts came out in 93 for the IDI.

Here's the write up on how to wire in the 3G, you should be able to figure out your wiring from it:

How to: 3G install for 83-92 IDIs