1987 Ford F150 ignition switch

137,000 MILES • V8 • 2WD • AUTOMATIC
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THELONGROAD1
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Hi I just replaced the cylenoid switch in my truck but when I go to start it It will turn over but when I take the key out of the ignition It will still be trying to turn over. Could it be the ignition switch thats gone bad?
Jul 29, 2008 at 9:47 AM
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BLACKOP555
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sounds like that ccould be the problem, take out the cylinder and try to turn it with a screw driver, does it still stick when switch is turned back?

does hitting on the housing help>
Jul 29, 2008 at 12:26 PM
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THELONGROAD1
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Ok it's not the ignition switch so what else could it be?
Jul 29, 2008 at 3:41 PM
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BLACKOP555
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whats the results you found?

tell me what happened when you used the screw driver and hiton the cylinder.
Jul 30, 2008 at 1:53 AM
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THELONGROAD1
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Well I taped on the solenoid switch with a wrench and it stops. but some times when I try to start it when I pull the ignition back into the run possition it stops, and other times it won't.
Aug 4, 2008 at 11:22 AM
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BLACKOP555
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you may need a new solenoid then, sounds like it may be sticking.

when you put the new starter relay on make sure the battery is fully charged, if not you will ruin the relay in no tiem at all.
Aug 5, 2008 at 1:29 AM
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THELONGROAD1
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It's brand new, I even took it and had then switch it out for another one and it did the same thing.
Aug 5, 2008 at 8:41 AM
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BLACKOP555
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but tapping on it causes the starter to stop staying engaged?

when replacing each time do you use a fully charged battery with clean connections and good grounds? if not it gets too much amps and it welds the plates together causing it to fail.
Aug 5, 2008 at 1:23 PM
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THELONGROAD1
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Ok I just found out the altinator isn't getting a charge could that be why the solinoid is staying engaged?
Aug 8, 2008 at 7:38 PM
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BLACKOP555
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shouldnt have anything to do wiht the solenoid, are the wirings grounding out on eachother? it just charges the battery, if the battery is low and your trying to start a vehicle with anew solenoid youll trash it in a hurry.
Aug 9, 2008 at 2:52 AM
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BAD_ACID
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I have this same problem. I have tried 3 different relays. The battery is fully charged, the ignition wire to the "S" terminal is going on and off. If I tap the relay,(on the fender), the starter disengages.
Dec 2, 2009 at 9:21 AM
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MIKE H R
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disconnect the s wire and check it with a light tester when you turn the ignition on to start then the light should light up. When you release the ignition switch then the light should go out. If the light stays light then there is feed back from another sourse. Check for a good ground. The relay needs a good ground to work properly. if not sometimes there is residual feed back to the the terminals.
Dec 4, 2009 at 3:52 AM
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BAD_ACID
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Thanks for the reply. As I stated in my post Ihave tested the "S" wire to be sure the switch is functioning properly. I'll check the ground and make sure that the relay is well grounded. That sounds like a possibility.
Dec 7, 2009 at 3:14 AM
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BAD_ACID
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Finally solved this. After replacing the relay 3 times, checking the switch to make sure power was being turned on and off to the relay, cleaning all the connections, of course being sure the battery was fully charged. I finally removed the starter and took it to Kragens, since it had a lifetime warranty, I had them test it. They insisted it was good. I said to hell with it and bought another starter and relay anyway. Went home and installed them. The truck starts perfectly now. My only guess is that there was something wrong with the old starter, causing it to draw too much power & weld the relay repeatedly. Kagens test seems to be, if it spins, it must be good. This is the second time I have replaced a starter they insisted was good. The first was on my daughter's Mustang. The starter would not stay engaged, but they insisted it was good.
Jan 25, 2010 at 5:10 AM
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BLACKOP555
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sometimes it bench tests good but isnt due to the way its mounted. might have a short or a bad brush that when mounted in vehicle it doesnt work but does when bench tested.

relays would weld shut if the starter is jammed mechanically not electrically. or if the battery level is low and you try to start it.
Jan 25, 2010 at 6:38 AM
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BAD_ACID
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After checking everything, following all of the advice given on this site, un-mounting remounting the starter. throwing up my hands in disgust & spending $60 on a new starter when there was nothing other than my gut instinct to tell me it was the problem, The truck starts, and the starter disengages when I release the key. I do not think you should be so fast to discount the starter as being the problem.

The test method does not place any load on the starter, its not turning anything. I'm sorry but you will not be able to convince me that the starter was not the problem all along.
Jan 25, 2010 at 8:03 AM
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BLACKOP555
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wasnt stating that. read what i said how it could have tested good but been bad.
Jan 25, 2010 at 1:57 PM
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BAD_ACID
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[quote:6579207e2b="blackop555"]
relays would weld shut if the starter is jammed mechanically not electrically. or if the battery level is low and you try to start it.[/quote:6579207e2b]

What I was saying was neither of these conditions existed. I had removed & reinstalled the starter, even though it had been working fine for a year or 2 before the initial problem. I checked to be sure there was not a lose bolt or something causing it to be improperly aligned. The starter was not jammed mechanically. I charged the battery fully before attempting to restart it after the second relay install. The third relay included being sure the relay was well grounded.

It's fixed now, and I'm happy. Thank you for all of your help.

My point being don't discount the possibility that the starter may be bad, even though it turns over the truck.
Jan 26, 2010 at 3:32 AM
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