Starter switch hot

[Art Ebeling]

I am working on a 26 that will start but turns over pretty slow but the starter will only drag if tried again a second time and the starter switch gets red hot. The cable to the battery gets hot also. I cleaned all the connections, same thing. The starter does not feel hot. Bad starter? Art

[TXGOAT2]

It could be a starter problem, but it could be the switch or the connections to the switch. If the starter switch gets very hot it is probably damaged. If the cables are the correct size, they should not get hot, and the switch should not get hot. NOTE: The starter is not designed to operate for more than about 10 seconds at a time. Grinding on it will overheat it, and will over-strain the battery. If the engine does not start in about ten seconds of cranking or less, stop cranking and let the starter cool down while you determine why the engine won't start. For the starting system to work as it should, all the parts, including cables, switch, battery, starter, and all ground points must be in good condition. The battery must be of adequate size and in good condition and fully charged. The engine needs to be in a good state of tune so that it will start readily, and the generator needs to be working as it should to keep the battery in a good state of charge.

[TXGOAT2]

The starter can get hot internally and still be cool to the touch on the outside. The starter should not be operated continuously for more than 10 seconds at a time without letting it rest for a minute or so before trying again.

[TXGOAT2]

If the timing is advanced too far when cranking the engine, the engine can fire against the starter. An easy way to check for this is to crank the engine with the ignition key off. If it cranks faster, the timing needs to be retarded more while cranking.

[Moxie26]

Are you using the proper size 6 volt battery cables?.... Just by looking, they are a thicker diameter than conventional 12-volt battery cables.

[Jerry VanOoteghem]

Does the cable from the starter switch to the starter get hot as well? If it does, then the problem is likely in the starter. If not, then the issue is maybe within the switch itself.

[John kuehn]

Do you know if the starter has ever been gone through? That could be the issue. Original starters and original radiators wear out after nearly 100 years. From what you’re saying it sounds more like the starter than the starter switch.

[speedytinc]

Original or repop type replacement switch? Repops regularly fail/burn out.
From what i have seen failures are a matter of when.
Originals can be easily refurbished if the bus bar is fairly solid.

[mtntee20]

When considering battery/starter cable size, one needs to know maximum amperage and length of the cable.

From a reliable model T source: 6 volt starting amperage may well exceed 250 amps and maybe as high as 300amps. For 12 volt systems cut those amperages in half.

Remember, KEEP the cable length as SHORT as practicable. Longer cable will need to be a larger size.
Remember, the LOWER THE NUMBER means LARGER cable AND HIGHER the number means the cable will be smaller.
There are many color coded graphs that coordinate amperage, length, and size. Google it.
ALWAYS use larger cable than you think you will need. The added safety margin just may make a BIG difference when you need it most.

[Craig Leach]

Hi Art,
Try doing a volt drop test to isolate the issue. You will need help with someone to push the switch. Set your multimeter to DC volts & test along
the circuit. Battery to cable, cable to switch, across the switch, switch to starter. When you put the test leads on each section you will get no
volts until the switch is pushed. If you get more than a few tenths of a volt when cranking then you have resistance in that part of the circuit.
If you get several volts then you have high resistance in that part of the circuit. Resistance x volts & amps + heat.
Craig.

[speedytinc]

Try a jump test between the 2 starter switch terminals. (Heavy cable or jumper cable)
That will rule in/out the switch & starter.

[big2bird]

I was just posting that. Lol

[speedytinc]

Try a jump test between the 2 starter switch terminals. (Heavy cable or jumper cable)
That will rule in/out the switch & starter.
A hot switch tells me insulators grounding or a bad internal connection.

[Jerry VanOoteghem]

I am working on a 26 that will start but turns over pretty slow but the starter will only drag if tried again a second time and the starter switch gets red hot. The cable to the battery gets hot also. I cleaned all the connections, same thing. The starter does not feel hot. Bad starter? Art

Art,

Several folks here have tried to help you. Do you have any feedback for us?

[Art Ebeling]

I took both cables off of the switch and cleaned the terminals and cable ends. they were corroded. I checked the switch with an ohmmeter and it worked correctly. After putting it all back together and several starts the starter button did not get hot and the starter turns like it should. I think I had a combination of corroded connections, combinded with a freshly rebuilt tight engine and too many attempts to get it started. Art

[TXGOAT2]

Automotive starters have a short duty cycle. That was true in 1912 and it's true today. 10 seconds of continuous cranking is about the limit. Wait a minute or two after ten seconds of continuous cranking before trying again. The engine should start almost instantly. The battery, starter motor, and the starter switch are not designed for extended engagement.

[Moxie26]

Clean fresh connections means a lot, ... positive and negative cables

[TXGOAT2]

Indeed they do. Beyond that, the engine needs to have a good electrical ground to the frame.

[Charlie B in N.J.]

Do you have a braided ground cable? They lose conductivity and heat up. If you have one check it. Had to replace mine for that reason and the cranking improved. The starter is of course the load but you say it's not getting hot. Right now I'm with wiring/cables.

[Jerry VanOoteghem]

I took both cables off of the switch and cleaned the terminals and cable ends. they were corroded. I checked the switch with an ohmmeter and it worked correctly. After putting it all back together and several starts the starter button did not get hot and the starter turns like it should. I think I had a combination of corroded connections, combinded with a freshly rebuilt tight engine and too many attempts to get it started. Art

Happy to see you've got it solved

[Art Ebeling]

Do you have a braided ground cable? They lose conductivity and heat up. If you have one check it. Had to replace mine for that reason and the cranking improved. The starter is of course the load but you say it's not getting hot. Right now I'm with wiring/cables.

Yes it does have a braded negative cable. I will get it replaced. Art

[Scott_Conger]

After putting it all back together and several starts the starter button did not get hot and the starter turns like it should

This being true, you do not need a new ground cable - also, no matter how "ugly" it is, if a braided ground is clean on both ends/connections, and has no broken strands, it cannot do anything other than conduct voltage/current as though it was brand new.