I'm the proud new owner of an '89 F250 with a 7.3l and a C6. It started and ran fine for a few days and then decided to stop turning over. I'm able to jump the starter solenoid from the big posts as well as the small ignition post to the big post. I'm assuming this rules out the solenoid. I noticed yesterday that I don't have reverse lights, so everything seems to point to the neutral safety switch. Is this a safe assumption? I don't have a repair manual yet, so are there any replacement instructions online?

 

Use the search function here in this forum and you'll probably find some instructions. If not I'm sure someone here can tell you how to do it! The guys on here have taught me how to do things to my trucks that I never dreamed I'd be able to do! There is a wealth of information in this forum! Welcome!

 

when you turn the key to start position, do you feel the return spring tension?
if not, my money is on a broken ignition switch actuator.
the NSS is mounted to the side of the trans behind the shifter arm.
while it is possible for it to go bad, i have never seen one go bad.

 

THE NSS went bad in my dump truck causing a no crank situation. I just bypassed it by jumping the 2 wires at the switch (red with blue stripe maybe)

 

Is that the device that won't allow me to start my engine in neutral? Very much a PITA when you are going 60 MPH down the highway and the engine stalls due to a fuel tank running low and you can't just shift into neutral and crank the engine. You have to pull over to the side of the highway with no PS and no brake booster. It could potentially cause an accident. I have often wondered how it could be bypassed and it's true purpose.

 

No the NSS is to prevent it from starting in gear. It should start in both Park and Neutral but not in any other gear.

 

Never mind. I tried it in Neutral at lunch and it worked on the 5th turn of the key. I think my ignition switch and connecting rod hate me. Oh, yay for more projects.

 

Do like bashby says and jump the two red wires at the NSS (C6 only). If it then starts the NSS is bad, if not look towards the ign switch or key switch linkage.
Should you need to replace the NSS here is a brief description.
Remove outer lever retaining nut and the lever.
Remove the two NSS retaining bolts and remove the NSS.
Fit new NSS and retaining bolts but do not tighten.
With trans shifted to Neutral insert a No. 43 drill into the alignment hole (just above the shaft). Now tighten the bolts to 55-75 INCH lbs.
Remove drill and reattach lever and nut.

 

Even easier then that, by pass that silly thing.

 

whats this im reading? my eyes must be deceiving me.this sounds strange coming from "Mr.stock"

 

Thanks for the help all.
Are you saying when I turn the key to start, does it spring back to run when I let go? If so, then yes it does that.

I'm pretty much an electrical novice. When you say to jump the two red wires, do I just connect them to each other as they come out of the switch? Can I do it on the other side of the connector?

 

I do have "some" room for invisible imperfections

 

Don't cut any wires. Temporarily, using a paper clip bent into a "U" shape, you can push the clip in where the wires enter the plug. This will connect the circuit, bypassing the NeutralSafetySwitch. This process is called back probing. This will get you running until you can replace the switch.

Should be the 2 red wires.

 

So it turns out it was the NSS. I just got finished rigging up a deadman and a manual switch for the reverse lights. Thanks for the help.

 

So I figured I might as well bump this old thread that's already got a bunch of information about the NSS as I believe that is where my problem is.

I've got a 1987 F250 C6 that only starts in drive. Am I right in thinking my best lead for tracking down and fixing this problem is probably a misaligned NSS? Or is there something else that could be causing it to NOT start in P N R but only start in D?

Thanks for any help!