Starter won't disengage
 

I'm having trouble with my 96 F250 4x4 460 auto. The starter is stuck engaged. I went to start the truck and the battery is dead. I went to jump it and as soon as I touched the terminals it started cranking. The solenoid is on the starter and the solenoid switch is on the fender. The starter is about 3 months old. Any help would be appreciated. Thanks.

My guess would be a bad fender mounted relay.

^^ most likely hes right ... had the same prob w/ my 85 and that fixed it ... and in a pinch beat it with a wrench to get it to shut it off lol

Ok this going to sound weird but I had an E 150 that did the same thing, replaced everything and still it did it. Finally I happened to catch a glimpse of the bottom of my battery cable terminal and it was broken. Replaced it and it never happened again. Ask the ford parts counter guy and he said this happens sometime, the voltage increase when the electricity jumps (sparks) across the gap created by the broken terminal can slightly weld the contacts in the relay in place. I don't know if was blow'n smoke or not, I just know it worked.

If it's stuck engaged, it would be easy enough to troubleshoot. Unhook the small wire that goes from the fender mounted relay(solenoid) to the starter mounted solenoid. When you hook the charged battery back up if it still cranks, it's the starter mounted solenoid. If it doesn't crank with that wire unhooked it the fender mounted relay.

Learn from my mistake.

When you get the new solenoid, do your self a favor and get the "Heavy duty" $20 one. Don't go for the $12 Auto Zone special. I bought the $12 one. It stuck again a week later, took it back and got another one free under warranty. It stuck again a few days later. I went back, spent the $20 on the heavy duty solenoid and haven't had a problem since.

Q

Today I replaced the fender mounted solenoid switch. $24 Napa Echlin. Didn't fix the problem. I'll try the starter mounted solenoid tomorrow. Thanks for the ideas.

If memory serves me right, this may have been discussed a looooong time ago. One poster suggested that a weak battery may cause the relay not to disengage. Not sure if makes sense, but I would probably have the battery checked to see if it is low on amps/volts.

i know my problem when my starter wouldnt disengage was a result of my stupidity..... my wires were on the wrong sides. i switched them over and bingo!

Troy, This happened to me in the fall on my E-350 I was in a hurry and had used an aftermarket relay, they were set up different and it drove me nuts. I happens. Glad you found it