The Stovebolt Site Forums The Parking Lot Big Bolts Key off, starter motor continues to run

Hello to all truck electricians,

i am almost done with my C60 and almost everything is working :-)

But I need your advice.
When I start the engine longer it keeps turning even though the key is out of the ignition. Really bad.

I have my starter and siren running through a Cole Hersee 24059 Continuous Duty SPST.
I had no data from the relays at the time of installation.

The document states:

750 A Make and 100 A Break
Int. ratings: 10 sec On 30 min Off

Now I suspect because I turned the starter too long (longer than 10 seconds), the relay stayed closed and the starter continues to turn even though the key is out. Likewise the siren.

According to the old siren wiring diagram, a Cole Hersee 24023 12V Intermittent Duty Solenoid SPST was installed. But it has almost the same data:
Int. ratings: 10 sec ON, 20 min OFF.

Where is the error, I have not yet fully understood?

I have attached a picture of my starter wiring. I read that you don't run the current flow for the starter (terminal 15) through the ignition switch, that's why the relay.

There must be a relay that can do this?

Thank you very much in advance.

Greetings Brian

The starter motor has it's own relay, it is known as the starter solenoid and is the "can" mounted on the top of the starter motor. You should not need the extra relay in the starter circuit but if you choose to use it won't hurt anything. If it were mine I would try a new relay and wire it so it is dedicated to the starter, it appears as though the relay is sticking, or it's a "latching" relay and incorrect for that application.

I agree.

I looked at the Cole Hersee 24023 and the 24059, they are not a latching relay, you have either a bad relay or the signal wiring is keeping it energized, check for voltage at the small studs after you turn the key off-should have no voltage there.

Ok, thanks for the tips.

But what do the dates mean?

- 750 A Make and 100 A Break
- Int. ratings: 10 sec On 30 min Off

Does the starter motor continue to run after the engine starts? If the engine doesn't fire, it's possible for the load of cranking the engine on the pinion gear to keep the gears engaged, and also keep the solenoid contacts closed, even if the voltage to the solenoid is removed by turning the ignition off. Tune the engine so it starts quickly and unloads the drive gear, and the problem will disappear. I've encountered the problem several times, and making the engine start reliably always makes it go away.
Jerry

A 24059 continuous duty should be fine for your siren or any other accessories. You really shouldn't need an additional solenoid for your starter. However if you want an additional solenoid to save your key switch, a 24023 would be in order. But you will need to have two separate solenoids. My fleet of Diesel trucks are wired like this. A type 24059 for the heater etc and a type 24023 in the starter circuit. From your key switch a wire from the accessory position goes to the 24059 and a wire from the start position goes to the 24023. You cannot use the same solenoid for both accessories and starting. If you do not understand the English, send me a personal message with a phone number and I will explain in German. Translation programs are not very good with technical terms.

If in fact the siren and starter are wired as he has posted, the siren is not activated through the 24059, he is showing that the terminal is used as a junction and the relay is only triggering the starter solenoid. Not sure if that is how he intended to draw it?

Two relays are used for the siren and for starting the engine, independently of each other.

The siren has its own 24059 and is activated with a switch from the interior.

The starter itself is connected directly to battery +.
I use the 24059 only to save my ignition switch. I did not run terminal 15 (hot key, is that what it's called?) to the Ignition terminal for the starter, but run that initial voltage for the starter through the relay.

I hope that I could explain it reasonably.

Where exactly is the difference between the 24059 and the 24023?
Thank you :-)

Translated with www.DeepL.com/Translator (free version)

Once again- - - -does the engine start? It's possible the problem is a mechanical one in the starter, like a weak solenoid plunger return spring, not electrical.
Jerry

No, the engine did not start.

The difference between the relays, one of them is intermittent duty or designed for on and off use, this would be ok for the starter circuit. The other is continuous duty, designed to energize an item that will be on for more than 30 seconds at a time, that would be ok for the siren. I would not worry about either one at this point in time, you need to diagnose the problem with the starter circuit first.

It's possible, but not very likely given the 100A break rating on the relay that the contacts are welding together and can't open. Breaking a circuit is harder on contact points than closing, thus the big difference in rating on the relay. But again, the solenoid coil on the starter would draw way less than 100 amps. It's easy enough to test by monitoring the voltage at the coil terminal on the starter solenoid. If it stays hot when you turn the key off, then the relay is bad.
Like Jerry said, the starter solenoid itself may be gummed up.

I have encountered this exact problem several times. While the starter is cranking the engine, the torque load of the starter pinion binds the gears together tightly enough that the voltage to the solenoid windings can be removed (turn the key off and remove it) and the starter will continue to crank. It's in enough of a bind that the gears cannot disaengage and allow the solenoid plunger to back away from the button that engages the electrical contacts at the back end of the solenoid. The only way to stop the starter from turning is to disconnect a battery cable. TUNE THE ENGINE SO IT WILL START QUICKLY AND THE PROBLEM WILL GO AWAY. Once the engine fires, the flywheel gets ahead of the starter pinion gear and allows it to disengage.

If you continue to ignore my advice, I will not contribute to this thread any further.
Jerry

Thank you very much for your help. I would never have thought of the possible problem with the starter. Thanks Jerry.

I will check the voltage at the relays.
I'll try to fix that problem in the next few days, get the engine set up right and let you know how it went.

Greetings Brian

Hello to all and especially Jerry,

Update:

I was able to solve the problem.
First, I had the Cole Hersee relays mounted with the "head/imprint" up. According to Cole Hersee the relays should be mounted like this. The inside contact pin is pushed down by the spring and gravity helps as soon as the tension is removed.

And, as Jerry advised me, I was able to get the motor set up well so that it starts fine.
Thank you all for the help. You guys are awesome.

Greetings Brian

Translated with www.DeepL.com/Translator (free version)

We're always glad to help a fellow stovebolter, no matter where he/she might live. Enjoy your truck!
Jerry