This is my first post so I apologize if I don't use the correct terminology. I have a 72 f250 camper special that I recently rewired with a painless wiring harness. I hadn't installed the carb yet but after I finished installing the wiring harness all the lights, wipers you name it anything electrical worked. It turned over as well. I put on the carb today and we got it running for a little bit but the starter wouldn't engage so it kept spinning. I unhooked the positive terminal from the battery and the starter quit spinning. When I put the positive terminal back on the post there was a big spark and nothing would work no more. No lights wipers or anything etc. I checked all the fuses and only one 30 amp fuse was blown which went to the horn. We slapped a new battery (because after that the previous battery would start to boil when put on the charger) in it and still nothing. I also changed the starter. I used the test light on the starter solenoid and was getting power just to the post which was hooked to directly to the terminal. Then put the key to the on position and had power to the starter "S" and ignition "I" posts. The wires leading from those posts had power as well. I tried by-passing from the battery post to the starter "S" post to get it to turn over and still nothing. The only other wire hooked up on the battery post of the starter solenoid besides the terminal wire is the wire that connects to a "Maxi-Fuse" made by painless which I'm not sure what it replaced on the original truck but, the maxi fuse still has power going in and out of it. I have no power to the fuse block. I have no power anywhere but, I'm not sure why switching the key to the "on" position still opens power to the "S" & "I" post on the solenoid. Does anyone have any suggestions? Any help would be greatly appreciated! This is my first pickup and we had it fire up a couple of times before everything shut down so, that gave me a little hope but now it's left me wondering. I suspect that it might be the wire that connects from the solenoid to the starter but, what effect would that have on any of the rest of the electrical not working? Thanks!

 

I would call Painless & tell them your PAIN
I assume no burnt wires .
There may be a factory resistor wire from the ignition ( PINK or PINK/ WHITE ) or a fusable link connected to the solenoid . They may have burnt into quickly & quietly without any obvious damage .
Now these may not be the problem , but sometimes funny things happen that make no sense & that is part of the problem ,
I say this because I do not know what else it could be at the moment........CALL painless tech...........
For some reason as I read ur problem I momentarily thought of a bad/no ground............situation.......I don't know........

Welcome & Good Luck

 

If you are using the original Ford start relay sometimes referred to as a solenoid, it isn't. The 'S' and the "I" terminal should only have power when the key is in the start position, never when it is in the run position. If you have current to the "S' terminal with the key in the run position, you have your ignition switch wired wrong.

 

I have never used an aftermarket wiring harness but as stated above, you should never have power to starter solenoid with the key in run. The factory harness sends battery power to the fuse panel and from there to the ignition switch. Then with key in start, power goes from ignition to the starter solenoid. Is that how the Painless is set up? Did you check each system as you were wiring the truck? And do you have a wiring diagram for the Painless? When I wired my 72 f250, I ended up with two minor problems that I had to fix, and diagrams help a lot.

 

My limited knowledge is a relay is an electrical switch , a solenoid has parts that actually cause a magnetic field to physically move parts , as I believe our Ford solenoids do . You can reportedly take one apart to fix it by cleaning & then turning over a disk inside and it will work . I think the disk is the part that moves .
Dennis Carpenters has it listed as a solenoid.........
I asked in a recent thread what is the amperage rating of one & got no response

 

The term solenoid and relay have been so mixed together in the automotive world that they are used interchangeably. But I prefer to call parts what Ford called them. That way there is no mix up on what someone is talking about. Relays are basically electrical switches to use a small amount of current to control a large amount of current. Solenoids do nearly the same thing, but they impart motion to another part in the process. The Ford positive engagement starter uses a start relay, "Fords words". The Delco type starter as on 429's-460's and the aftermarket types are solenoid engaged starters.
Don't go by what Dennis Carpenter calls anything those people just make up part numbers sometimes.
Aircraft relays are marked with the amp ratings automotive stuff isn't, but a Ford positive engagement starter can draw up to 200 amps, so the relay is capable of that much current for a short time at least.