My 85 6.9L F250 (manual) occasionally won't start. With the key turned to the start position nothing happens. I do get a notification light in the glow plug / ready to start 3 bulb assembly that always comes on when I start the truck so turning the key is doing something. Other than that its like the key isn't in the start position - no noise, to turning of the engine, nothing. Usually all it takes to solve the problem is to open and slam closed the driver side door and if that doesn't work pop the hood. Try the ignition again and its like nothing was ever wrong.

Lately the problem has been more frequent. My usual tricks aren't as effective and I've had to try other things (tapping the steering column, pumping the clutch pedal a few times, just letting it sit) which may work every once in a while but nothing consistent.

Battery connections are good (will scrub terminals next break in the weather just in case). The battery has a good charge and can power all accessories. I was thinking maybe the clutch pedal ignition lock. Any suggestions where else to look?

 

Clutch pedal has to be depressed to start on these trucks,right? If so it could be the switch on the pedal.

 

Things I would check/do
Clean battery terminals.
Take all wires off on the solenoid on the passenger firewall, shine them up and the solenoid connections themselves and reconnect.
Check ground wires to block and to frame, shine them up if needed.
Pull the fuse on the ignition switch circuit and check for corrosion.
Spray a little electrical cleaner in clutch switch and make sure wire is connected good.

Why do I feel like I am missing something...

 

Not sure if it might be related, but I did just replace the heater core which was spraying some coolant in the engine bay down the firewall on the passenger side. Not sure if any critical electrical connections are in that area.

 

the starter

 

possible that the starter relay going out? ignition wire come loose from relay or soleniod? corrosion @ the starter on any of the wires?

 

I had about the same problem last year. This spring when I could finally get into it I found out that the terminal into the starter selonoid had come lose. (the one mounted on the starter) After tightening that up I haven't had THAT problem again.

 

Could be that damn safety switch for the clutch pedal. Disconnect it!

Or since you had a coolant leak, maybe screwed up some wires for the starter.

 

mine was doing the same thing, it was a combination of two things, first the c shaped clip that connects to the pushrod that goes to the ignition module was broken, and then my selenoid to body ground was bad

 

99 out of a 100 times electrical problems are grounds... That goes for all vehicles not just our old trucks.

 

Had this same problem on and off all summer long on my 1990 F 250 7.3. It was the ignition switch that's bolted on the column had slightly moved over the years with in the adjustment range. I simply readjusted and re-torqued the bolts and has worked fine ever since.

 

on one of mine the ignition switch (at the base of the column) actually cracked...became totally intermittent; on another one I had the firewall flex issue and could not always get the clutch far enough down to close the saftey switch.

 

Everything is so loose in my steering column that I have to reach my finger on the top of the column and push that little rod forward, after turning the key all the way on. Then I have a push to start button.

 

I have a 2002 7.3 F250 Auto with the same problem I found that if I keep turning the key to stop and run it will start cant find out why its doing it. It doesn't do it all the time most of the time it starts right up

 

Well the batteries finally stopped holding a charge which gave me an excuse to take a closer look at the battery cables. After peeling away some of the sleeves I saw a few bulging spots on the positive cables. So while I'm waiting on Napa to restock the second battery I figured I might as well take the opportunity to take care of this before it causes any problems down the road.

While pulling cables I realized I might be able to solve my original starting issue, so all the wires on the starter system came out too. Probably didn't need to, but I took the starter out because I was having issues removing the nut holding the small wire on (the one from the relay). About two hours later I finally figured out how to slip a socket / extender bar / u-joint on the 3rd bolt on top. So now I've got all my wires / cables / batteries out of the truck, along with the starter.

Since everything looks stock (and pretty poor condition), time for new wires all around. Thinking about going 3/0 for the cables, which might be overkill but not much more expensive in the grand scheme of things. With that said, a few questions:

1) Probably go with solder terminals for a few reasons, but the main one being I can't find any tools or shops locally that I trust to adequately crimp the connections. The old connections were soldered in and there were no issues at the point of connection. As long as I go through the right soldering procedure and seal up with adhesive shrink wrap should I bother considering crimping?
2) I'll go with standard straight terminal connections on the ground wires but was thinking about marine posts / ring terminals for the positive cables. More in the interest of future expandability with accessories than anything else. Any issues other than the nut coming loose (probably will use a lock nut instead of wing nut)?
3) Is it worth running a ground wire to one of the starter bolts?
4) I assume it is a ground connection between the starter solenoid and starter body, but whatever it is, it is bare wire with a loose braided sleeve around it. Thinking I might run insulated wire instead and maybe connect the extra ground mentioned above - thoughts?
5) Any suggestions on gauge thickness for wires to / from the starter and GP relays, or just stick with stock (some of the stock wires seem a little thin to me)?