The 86 F250 I have is giving me all sorts of issues. Got the truck with a bad motor. Long story short is i cant get the starter issue resolved. Here is what I have tried/changed:
Starter (from my DD so i know its good)
Starter selinoid (done this three times now)
Positive battery cables (from battery post to selinoid then from selinoid to starter)
Negative battery cable (grounded to block)

First off i took the truck out in the sand dunes to see if the 4x4 and everything worked right. Well it did, but the truck died on me when i went to leave. I touched the selinoid on the fender and both positive cables were hot. The key would do nothing, nor would jumping the selinoid.
I proceded to change the selinoid with a new one. This time it starts right up, but the starter kept running as the motor did. Shut it down, but the starter kept it going until i got the cable off the battery (45 sec at most). This time i went and got the more expensive selinoid and changed the starter with the known good one. Starts right up and starter is not running. I shut it down and hooked up my coolant flush kit and went to start it. I get nothing but a click. Not the clicks like a dead battery, but a click like a bad selinoid or starter.

Now, my question is, why is it eating up selinoids? Or is there somewhere else i should be looking? Is there a relay to check?

Oh and i forgot to mention, when i had someone turn th ekey while i was under the truck, i could feel the starter "click" also, not just the selinoid. Not enough power down there? Seemed like the battery was just fine...

 

Try temporary installing a push button for the starter. Get a button and some wire and run a wire from the pos side of battery to the button and then to the pos side of solonoid. Make sure you hook to the terminal that is controlled by the key. Doing this will bypass the key starting it. If your problem goes away then theres a problem in between the key and solonoid. It could be the ignition itself or a wire issue.

 

You can just use a small piece of wire (to jump 3 & 5).

From Franklin2's diagrams:

 

Jumping from number 3 to number 5 does the same thing as if i turned it at the key. Just clicks. This is the third relay so it cant be bad, can it? Why do i keep burning through them?

 

You have a bad ground to the block, AND the body. Remove the main ground from the block, and clean it until it, and the block where it fastens, shines like new money. use a new bolt, and some dielectric grease on the connection. clean the battery terminals, and coat them with dielectric grease. run a 10 guage wire from the neg batt cable to the bolt that holds in the radiator at the top. run a 10 guage wire from the bolt on the bottom of the wiper motor, and fasten it to the block somewhere. last, check the ground strap from the firewall over by the heater, and make sure it is fastened to the intake. Whenever a starter runs on, there is a bad ground.

 

I only have the ground to the block. I will add the others today. Will having a 2 awg wire for the positive connection to the selinoid and the starter be too big?

 

you should be ok with that, altho it is a bit large. If it were a 6 volt system, that would be perfect.. When you put your motor together, did you paint it? if so, make sure to clean the paint off to bare metal where the ground hooks to it.

 

On another thread of mine the guy said his only came with the single ground to the motor from factory and he has no problems with his truck.

The motor was pulled from the junk truck with a bad trans. It then received the older timing cover, fuel pump, accessory brackets and v belt along with intake and carb. That's all. No paint, nothing fancy.

Truck started fine in my drive for a couple days, letting it run for a few and shutting it down. Problem started when I took it to the sand pits to make sure everything worked. That's when it died and hasn't started right since.

 

I am not sure if I have a ground issue or not. I sanded the block area clean and put on a new ground to there. I am going to add the other grounds(one to frame and one to body. Maybe on to fire wall as well) and go get new starter selinoid number four and see where that gets me.

 

Or a cheap "Made in China" starter solenoid, which is about all a person can find at *most* auto parts stores.......
I dunno, maybe they use a weak spring inside them that simply cannot force the contacts to break the weld they tend to form when they close, or maybe the contacts are made with too light of a copper content making them overheat and permanently welded together. Could even be a combo of both. These are rather simple little critters, I don't see how anyone could mess up production with such consistancy, but they do........

 

I just hope number four and the addition of new grounds will solve my problem. Going to do it now. I'll let you all know the outcome

 

A bad ground can do that. I just mentioned the push button because I have a wire issue between the key and solonoid on my truck and adding the button solved my starting issue. I replaced the ignition in my steering colum and still had the same problem until I added the button.

 

If all else fails try a new starter. They can ground out.

 

Did you adjust or replace the ignition switch on top of the column behind the dash?

 

Unfortunately if this one doesn't work that's what I'm going to have to do. I've spent money on all new plugs, wires, cap, rotor, new fuel pump, timing cover, timing chain and gears, edlebrock carb, air cleaner, headers, and now all positive, grounds and starter solenoids. Tired of spending money on a play toy like I am but it's going to be a blast when I'm done.