Something's Stuck!

[Sammyprgandy]

I have an '87 Ford F-150. I just replaced the alternator,battery and selenoid. I did that because something was draining the battery. Now,I hook up the positive to the battery and it gives a spark,starts welding the clamp to the post and begins to start the motor...even with the key in the off position! I let it start with the key in the on position and disconnected the positive,and the alternator would not hold the motor. What do I look at first?

[shawnlee28]

There was some kinda recall on the steering colum of those year trucks for electrical .I would start there.I would think the ignition system would have to be involved for a computer controlled truck to start the computer has to think the key is on,did it just turn over or actually start?

[Sammyprgandy]

I let the cable stay on long enough to see if it would start. It did start. Then I disconnected the positive to see if the alternator would hold the engine,it cut off. It is also soldering the positive clamp to the battery post,which makes me think that there is some sort of short or feed back to the battery that is not right. Is this a correct assumption?

[Matt167]

Check to make shure of the wiring to the solonoid, somthing is deffenetly crossed, probably going to be the battery cable that goes directly to the solonoid is hooked up wrong. My grandfathers truck had that problem with the steering colum electrical and, nothing worked when it went, no start, no turn over no nothing so, it's not that.

[Matt167]

Originally posted by Sammyprgandy
I let the cable stay on long enough to see if it would start. It did start. Then I disconnected the positive to see if the alternator would hold the engine,it cut off. It is also soldering the positive clamp to the battery post,which makes me think that there is some sort of short or feed back to the battery that is not right. Is this a correct assumption?

see my last post.

[lt1s10]

Originally posted by Sammyprgandy
I have an '87 Ford F-150. I just replaced the alternator,battery and selenoid. I did that because something was draining the battery. Now,I hook up the positive to the battery and it gives a spark,starts welding the clamp to the post and begins to start the motor...even with the key in the off position! I let it start with the key in the on position and disconnected the positive,and the alternator would not hold the motor. What do I look at first?

Go back to your solenoid that you put on, sound like the starter wires are hot all the time. If it wont doing that until you worked on it go back over what you did. the alt is not going to make the starter to turn over.

[HWORRELL]

Ya got the battery positive and the starter cable backwards at the solenoid.

[Sammyprgandy]

That has to be right. How stupid of me. I have three terminals. Negative battery,Hot battery and the third small post,(bottom Center) is bare. I never hooked anything to it. It is between the Large positive and negative posts. Now all I have to do is figure out which wire goes to it and I am in business.

[HWORRELL]

No ground on a Ford solenoid !!!!!!
battery positive cable..... starter cable......
and solenoid energize wire from ignition switch(small wire, red with light blue stripe)

[Sammyprgandy]

To note. I replaced the selenoid,because i thought this was an issue that was causing my battery to constantly fail. Looking back,I see that that was not the case,but it was. The selenoid was no bad,just miswired. I rewired the selenoid in the same configuration as when i took the old one off. That is what the issue was to begin with. Since the selenoid was wired incorrectly would it cause any of the following issues?

Battery not charging
Engine running hot
But also,if it was incorrectly wired from the beginning,would it not have had the same problem of not cutting off the engine as before? The only thing that i heard from the motor was a constant humming after turning off the ignition which sounded like a fan. Leading me to believe the engine had overheated,although the temp guage did not indicate this. Maybe because it doensn't work either.

[Sammyprgandy]

I disconnected all cables from the selenoid other than the starter,battery and the starter relay wire. It did the same thing. I swithed the battery and starter wire positions,same thing. It's like it's strait wired. Bad selenoid?

[HWORRELL]

May have welded the contacts in the selenoid together, a very weak battery will do that.....

[Sammyprgandy]

Thanks HWORRELL. You are more thank likely right. The selenoid is stuck open. But,would this cause the alternator to not hole the engine? How would that work? The alternator wire is on the same post as the battery,right? and should hold the charge needed to sustain power to the motor if the battery fails. So,even if the bridge to the starter and battery is constantly connected,once the batter is disconnected the alternator should pick up the motor and stop the charge on the battery,so the selenoid becomes a non-issue. Why,with a new and tested alternator,would this be the case of the engine quitting after the battery is disconnected? That's confusing. Bad wires? They look good. Poor connection? Feels tight and looks clean. Belt is tight and turning without a problem. Is this the selenoid,or keep looking?

[lt1s10]

Originally posted by Sammyprgandy
Thanks HWORRELL. You are more thank likely right. The selenoid is stuck open. But,would this cause the alternator to not hole the engine? How would that work? The alternator wire is on the same post as the battery,right? and should hold the charge needed to sustain power to the motor if the battery fails. So,even if the bridge to the starter and battery is constantly connected,once the batter is disconnected the alternator should pick up the motor and stop the charge on the battery,so the selenoid becomes a non-issue. Why,with a new and tested alternator,would this be the case of the engine quitting after the battery is disconnected? That's confusing. Bad wires? They look good. Poor connection? Feels tight and looks clean. Belt is tight and turning without a problem. Is this the selenoid,or keep looking?

you all reading to much in the job of the alt. until you get it running forget about the alt. the alt dont carry the motor, its charges the bat up. youve got a starter staying engaged, the best thing you can do with the alt. is unhook it until you fix the starter or you gonna burn up the alt up to. until you turn the ign on there should not be any volts at the starter, if you do have valtage at the starter with key off then go back up the wiring find out where its shorted. a ford starter will go bad an turn on it own sometimes, but its a matter of using the wiring diagram that danny sent you, you should be able to wire the sol.

[Sammyprgandy]

The battery,starter and used to be the selenoid are new. The wiring diagram is helpful,It is wired right noe with the starter and battery separated on two different posts. i will replace the selenoid and check the diagram to see if it is correct. Alternator should still carry the engine. That question is still on the table.