Only here a click when starting engine.

[forestb]

So my 62 C10 has been running and starting great. I was driving it on Saturday and parked and turned it off and couple of minutes later I tried to start it again and all I heard was a click. It didn't even try to turn over. I had over 12 volts on my voltmeter. I tried to use a jump pack to start it and it didn't help. Radio still worked. It is a 350 with a 700R4. Battery is fairly new and the alternator was rebuilt about a year ago. My initial thought is that I need a new starter motor. I am going to check all my wiring first but I was wondering if there were any other thoughts before I start replacing parts. I was also wondering if it is possible for the gear on the starter to not engage with the gear on the fly wheel or run into them when popping out. I found it strange that it didn't start and then 15 minutes it did start. Nothing was moved or wiggled. My only thought is that it cooled down and then it started.

[truckster]

There's a thick copper washer in the starter solenoid. When you turn the key, the voltage goes to the low-amperage side of the solenoid, creating an electromagnetic draw that closes the high-amperage side of the circuit. That contact occurs between the copper washer and two large contacts. After many cycles, carbon can build up on the copper and prevent the circuit from closing.

If you disassemble the solenoid, you can clean the copper disk and contacts with emery cloth and that should solve your problem.

[forestb]

Originally Posted by truckster

There's a thick copper washer in the starter solenoid. When you turn the key, the voltage goes to the low-amperage side of the solenoid, creating an electromagnetic draw that closes the high-amperage side of the circuit. That contact occurs between the copper washer and two large contacts. After many cycles, carbon can build up on the copper and prevent the circuit from closing.

If you disassemble the solenoid, you can clean the copper disk and contacts with emery cloth and that should solve your problem.

Cool thanks. I have a mini starter. Is it the same as what your talking about?

[HO455]

I'm of the opinion that you're suffering from the starter hot soaking. This condition is when the connections and or the insulation of the windings inside the solenoid start to fail. When cold the internal resistance of the solenoid is normal and the voltage at the solenoid is enough to fully pull the bendix out and engage the flywheel ring. When the solenoid is hot it's internal resistance is much greater and the volt drops because the factory 12 awg is too small carry the load required.

That wiring is quite long and goes through multiple connections. Starting at the main splice near the horn through the firewall plug, to the connection behind the fuse block, to the ignition switch contacts, to the neutral safety switch contacts, back through the firewall plug, and down past the exhaust and to the solenoid. That's over 8 feet of wiring, 9 connections and two sets of switch contacts. All of which when hot will have increased resistance which adds to the voltage drop at the solenoid.

When hot the voltage is applied to the solenoid after you've turned the key is only enough to move the bendix against the ring gear and not enough to force the starter gear out and engage the ring gear. Thus the click you hear. The starter gear must move enough to engage the ring gear before power is applied to the starter motor.

Having good connections everywhere and a good solenoid like the truck did when it left the factory will solve the hot soak problem.

Another common cure for less than perfect systems is to install a Ford starter solenoid in the starting circuit. When installed the start wire only has to operate the solenoid coil which only requires an amp or two. When the relay circuit is installed a 10 or 8 awg wire is run from the battery to one of the large bolts on the Ford solenoid. The other bolt is wired to the start post on the starter solenoid.

This is a common modification that has been popular for 30 plus years and there is lots of information on how it works it on the interweb. My Burban is currently suffering from this condition and I plan on adding a Ford solenoid set to cure the problem.

[forestb]

Originally Posted by HO455

I'm of the opinion that you're suffering from the starter hot soaking. This condition is when the connections and or the insulation of the windings inside the solenoid start to fail. When cold the internal resistance of the solenoid is normal and the voltage at the solenoid is enough to fully pull the bendix out and engage the flywheel ring. When the solenoid is hot it's internal resistance is much greater and the volt drops because the factory 12 awg is too small carry the load required.

That wiring is quite long and goes through multiple connections. Starting at the main splice near the horn through the firewall plug, to the connection behind the fuse block, to the ignition switch contacts, to the neutral safety switch contacts, back through the firewall plug, and down past the exhaust and to the solenoid. That's over 8 feet of wiring, 9 connections and two sets of switch contacts. All of which when hot will have increased resistance which adds to the voltage drop at the solenoid.

When hot the voltage is applied to the solenoid after you've turned the key is only enough to move the bendix against the ring gear and not enough to force the starter gear out and engage the ring gear. Thus the click you hear. The starter gear must move enough to engage the ring gear before power is applied to the starter motor.

Having good connections everywhere and a good solenoid like the truck did when it left the factory will solve the hot soak problem.

Another common cure for less than perfect systems is to install a Ford starter solenoid in the starting circuit. When installed the start wire only has to operate the solenoid coil which only requires an amp or two. When the relay circuit is installed a 10 or 8 awg wire is run from the battery to one of the large bolts on the Ford solenoid. The other bolt is wired to the start post on the starter solenoid.

This is a common modification that has been popular for 30 plus years and there is lots of information on how it works it on the interweb. My Burban is currently suffering from this condition and I plan on adding a Ford solenoid set to cure the problem.

So to test if what your saying might be the problem, i would first see if it starts cold, then drive it until hot and then turn it off and see if it will start right up again.

[HO455]

Usually after getting the truck hot you need to let the truck sit and "Heat Soak" for 20 or 30 minutes before the problem occurs. Once it occurs checking the voltage at the starter solenoid start connection will show if you have low voltage.

Once it occurs opening the hood helps to cool the solenoid quicker, as does hosing it down with water.

[forestb]

Would 20 min of driving do the trick

[HO455]

Yes that should be sufficient.

[forestb]

If I decide to purchase a new one is there a way of telling how many teeth I have on my flywheel by looking at the starting motor.

[franken]

Before throwing money at the issue or listening to people on here wanting to tell you what the problem is you should troubleshoot.
As mentioned above measure the voltage to ground from the S-terminal on the solenoid.
Adding another solenoid to solve a problem you don't understand only complicates things.

[forestb]

Originally Posted by franken

Before throwing money at the issue or listening to people on here wanting to tell you what the problem is you should troubleshoot.
As mentioned above measure the voltage to ground from the S-terminal on the solenoid.
Adding another solenoid to solve a problem you don't understand only complicates things.

Should I do this when it running or just with the key in the on position?

[franken]

Sorry, the key should be in the start position.

[Dead Parrot]

Something similar happened to me last summer. Drive it in hot weather. Stop. Click on restart attempt. Wait a minute or so. Retry would start.
Mostly stock 350/TH350. Had recently swapped to Hooker cast iron manifolds: https://www.holley.com/blog/post/eve...ust_manifolds/

These are closer to the solenoid then either the previous set of headers or stock manifolds.
Starter was only a couple years old and I don't drive the truck a lot.

My attempts to resolve so far are a new set of battery cables because the old positive cable was 25+ years old. Went with some that featured 2 gauge wire over the more normal 4 gauge. Also installed a home made heat shield over the solenoid.

Problem hasn't happened again but this was late summer so not sure if the hot engine + hot weather has repeated.

Another possibility is worn starter brushes. Symptoms fit. If it happens again, whack the front end of the starter a couple times with a length of pipe. If worn brushes, the impacts will often settle them enough to make contact.

[forestb]

What kind of voltage should I be looking for on the S terminal on the solenoid? And if it checks out does that mean o need a replacement/rebuild

[franken]

Ideally 12.6V if the battery is charged. Of course things aren't ideal so you'll see lower in real life.
Also, try using the starter, block and battery as ground points to see if the reading changes.

[forestb]

So my truck started up fine cold this morning. It’s the first time I have tried to start it after getting it home last Saturday. I took it for a 20 minute drive and it started up fine after that. I got it jacked up and on jack stands and was all ready to check the voltage but realized that I left my multimeter at home.(I don’t like in the same location that I work on my truck). So I will check the voltage next weekend.

[forestb]

So this morning I tried to do some voltage testing at the S terminal. If I am standing in a location where I can see the terminal I can not reach the terminal. When I am in the position to reach the terminal I can not see them. When I went to blindly put the multimeter probe onto the terminal it just started shooting sparks. I am not sure what happened but I don’t want to try it again. In retrospect I should have used alligator clips while the battery was unplugged and then put the multimeter to the alligator clip but hindsight is always 20/20. Maybe I will try that again later if I have problems again. What I did end up doing was remove the starter and open it up and use some emery tape to clean off the copper cylinder with grooves in it that the brushes/rubbing blocks rub against. It was pretty coated. I put it back together and it fired up fine. A while back I got a new motor for the truck and we used the same starter motor. Ever since I did that when I would start the truck there was almost a clunking sound. The mechanics said it was normal. Now that I have cleaned off that copper cylinder it now sounds normal.

[geezer#99]

That almost clunking sound could be the starter motor moving a bit.
You might need a starter brace like in this link.


https://67-72chevytrucks.com/vboard/....php?p=9035697

[forestb]

That could be possible but I kind of doubt it. The bolts were super tight when I tried to remove the starter. I could barely loosen them with a 3/8 ratchet. When I bolted it back in it i dough that I got it tighter than it was. My guess is that because of the dirty copper cylinder the electrical connection was intermittent. But it it starts happening again I will look into the brace. It is a mini starter, so it probably doesn’t have nearly as much weight to it as the stock starter.

[forestb]

Which terminal is the S terminal. I don’t see markings on any of them except for what looks like a H in between the 2 larger terminals

[forestb]

Photo