79 K10 starter won't fire. At a loss

[79 K10 Stepside]

My 79 K10 Chevy starter will not fire not a click or anything when I turn the key.

Here is what I have done - 3 years ago rewired the truck with Painless wiring no issues. Starter wiring hot wire to battery, same pole hot wire through 70 amp fuse (good) to fuse panel, Solenoid S terminal wire runs to fuse panel and on to Neutral Safety Switch.

Start intermittently would do nothing when I turned the key now nothing at all all other electronics in truck ok. Took out starter and had it checked..checked ok

Replaced Ignition switch above steering column, replaced Neutral Safety Switch, performed continuity check on hot wires to fuse and steering column through firewall, checked solenoid continuity to safety switch and was ok but noticed also got continuity on this line when I touched ground?? Wire inspected no damage, heat burn or fray??

Checked voltage at safety switch with key off nothing, on 7 volts?? Hot wire voltages ok.

Let me know if anyone has any other ideas??

[Jstock85]

Man! you got your hands full. The only things I can think of is a bad solenoid but you've checked that, a blown fuse somewhere but if you've all the above then a fuse wouldn't have slipped your mind. Only other i can think of is a bad wire somewhere shorting out but sounds like you've traced those as well. Maybe check your grounds. One may be loose causing a bad connection somewhere.

[79 K10 Stepside]

Thanks definitely a mess. I think I may go ahead and replace starter as solenoid may be intermittently bad. Only other thing I can think of is voltmeter which is indirectly connected via hot wire from alternator to fuse panel and exciter wire to voltmeter.

[Dead Parrot]

Before replacing starter, use a remote start switch to bypass the column ignition setup and test starter/solenoid.

Starter brushes near EOL can cause your symptoms. If brushes near end of life, tapping the bearing cup can cause them to make contact 'one more time'. Taking the starter off could have done the same thing.

A sector gear with the last tooth broken can also cause a won't start when key turned problem.

If it starts and runs using a remote start switch, suspect the sector gear, otherwise suspect the starter.

[79 K10 Stepside]

Thanks for the reply, great idea on the remote starter. I will try that before putting in a new one. All gear teeth on fly wheel and starter look fine. (bell housing is off so I can see the fly wheel)

[Dead Parrot]

The sector gear is a small plastic gear in the steering column that turns when you turn the key. If the last tooth breaks off, it can't pull the ignition switch to the start position.

[Jstock85]

Originally Posted by Dead Parrot

The sector gear is a small plastic gear in the steering column that turns when you turn the key. If the last tooth breaks off, it can't pull the ignition switch to the start position.

That thing is buried deep also! if you've never tore into a column take notes and a lot of pictures. A lot of small parts! first time i did mine the high beam extension stick and spring fell onto the floor and it was a PIA to put back together!

[79 K10 Stepside]

Update - Sector gear is good as I can see the ignition switch movement as I turn the key and it goes all the way to the end when I turn the key. (when it hits the end all power goes off to radio dash lights as it should because the power is all supposed to go to starter on spring loaded switch)

Tried to remote start on old starter and it would not work. Replaced starter with new one and it would not start. ugh Could however remote start the truck but that means I have a wiring or ignition switch issue.

Continuity checks give tone on all connections from starter to column switch. Hot wire from starter to ignition switch at over 12 volts suggesting the issue is the wire from s pole on solenoid to the steering column.

Question is continuity is only so informative as it won;t tell short depending or weak link in wire. If I do resistance on 14 gauge wire I guess that should narrow the issue but I do not know what readings I should expect.

Thanks for your help

[abig84]

something that often gets over looked is check your engine ground. most people always check the big postive wire and the signal wire. make sure the engine block is grounded to both the frame and the body or just run your own ground to the starter for diagnosis reasons

[Jstock85]

Grounds! good idea.

[79 K10 Stepside]

Problem Solved, Thanks to all for the help and suggestions. Checked voltage again at ignition switch again only got 3 volts. Ran a jump wire from firewall fuse panel solenoid wire to ignition switch. Manually with needle nose engaged switch and it started.

Knew where to look and found lose connection on the neutral safety switch plug which was spliced in with connectors buried under conduit and lots of electric tape.

Also found out ignition switch must be adjusted to exactly right position or it won't fire. New starter does work much better so glad I installed it.

Now to haul off the trash that has been building in my truck