The culprit - 1979 F150, 300 I6, NP 435 4 speed manual, pretty much a stock truck.

Truck has been turn key starting and running fine in the weeks prior. No signs of over heating or weak battery. I was at the store and it wouldn't start, had power but nothing happened with the key turned. We tried jumping it first and tapping the starter, nothing. We pull started it by popping the clutch, no problem, drove home fine.

I picked up a starter the next morning and replaced it, truck started and ran fine...twice. It was a no start later that same day. I managed to start it by popping the clutch and picked up a new starter solenoid (which I think is actually a relay in these Fords) and ordered a neutral safety switch just incase.

Replaced the solenoid, nothing. Tried to pop the clutch on it again, didn't work.

Today I did the battery posts and cables with a Battery Terminal Spreader & Cleaner and replaced the wire from the solenoid to the starter (should this wire show as getting power when the key is turned, because it didn't on my test light). Still nothing. I picked up the neutral safety switch from NAPA (our only local parts store) which I thought went into the steering wheel column someplace but can't find it, so it's still sitting in its box.

I have power, but turning the key doesn't do anything, no clicks or attempts by the starter to engage. Any suggestions on what to poke with a stick next?

 

The NSS mounts on the steering column for 73-77's

and mounts on the transmission for 78-79's

 

Well that makes sense then, when I was researching I think it was a thread here for a '73 or '74 that got me onto the possibility of the NSS being a potential problem, which is why I went into the steering column.

Do you know off the top of your head where on the tranny? Mine is coated with years of hydraulic fluid leaked from the plow hook up and I'll be scraping away a good inch of goo to get to it.

 

That i can't tell ya, i'm a 4-speed guy, i'm sure someone will chime in here in a sec...

 

Wait a sec! i just noticed you had a 4spd DUH!

Only the auto's have a NSS.

 

Why would NAPA list a

Neutral Safety Switch
Part Number: ECH NS6579
Product Line: Echlin Ignition Parts
IMPORTANT INFO: w/ 4 Speed M/Trans,Except Overdrive

when the transmission doesn't have one? They list a second cheaper one also for the manual. WTF did I buy?

 

If you touch a jumper from the batt positive to the solenoid's "S" terminal does the engine crank over? Disclaimer: Test in neutral wheels blocked....

.

 

I'll give it a shot, one minute. She's pointed at the wood pile right now so if she takes off on me it should hurt too badly...

 

Started right up with the key turned to 'on', no problem. Made a new odd noise. When I turned the key off the starter kept engaging, I was in the process of disconnecting the starter cable from the solenoid when it stopped on its own.

I think the odd noise was the starter continuing to run with the engine running. What's the next step?

(on an unrelated note, does anyone know how to stitch a finger back on?)

 

Well at this point we need to find out for sure if you have a NNS or not. If you don't have one then I would suspect the ign switch. On a related note make sure you have the correct wires going to the solenoid; IE: "s" & "i" posts. The wire going to the S post should only have power when the key is turned to the start position.

.

 

I'll go test them and make sure the wires are in the right spot.

 

Crossed wires, good call. started right up when I put them on right. I appreciate the outside views, I had already convinced myself it was a lot worse then it seemed. Good reminder to recheck the simple stuff

Anyone know what that supposed NSS I picked up is actually for?

 

I guess you're right, i didn't think Ford put a NSS on the manual trucks until the 80's.

 

Honestly I have no clue, and it wouldn't be the first time a parts store was wrong.

 

Glad it worked out!