Engine: 55 Studebaker Champion wont start when hot....

[cocos_03]

Hey guys I am new to this and just want to introduce myself: My name is Jason from Toronto and own a 55 studebaker champion. (will post pics soon).

Ever since I had the car, it always starts up without a problem at all when it is cold. If I drive it for more then a half hour and turn it off, my odds of it starting are very slim. The engine turns over but very very slowly as if it has no crank from the battery. I let it cool off for a half hour and it starts with no issues. I though I would get peoples opinions on what it may be. It is an original 6 volt and the car has 4000 original miles, 90% oringinal, including tires and has not 1 spec of rust on it.

Let me know what you guys think. Thank You

[55s]

Another 55 in Toronto! Excellent.

Slow turning over can mean several things. Remember they went to 12 volt cars one year after for this reason!

Here's a list:

(1) Battery weak. It has to be a fresh 550 cranking amps battery. (by the way, if you are careful, you can boost with a 12V and it will turn over quickly.)
(2) Battery cables and battery connections. Usually corroded, or have been replaced with 12V lighter gauge.
(3) Ground.
(4) Solenoid not letting all current through.
(5) Timing, if off, can slow it down.
(6) Starter motor. Brushes may need replacing or field coils in case may have expanded with oil and are rubbing on the armature when hot.

Do a search and you are likely to come up with more reasons!

[55 56 PREZ 4D]

Cables "NEED" to be AT LEAST 1/0. Better if they are 2/0. 1/0 cable is about 5/8 " thick.
Even if they are the correct size, they are OLD.
They may be corroded INSIDE the insulation, you can't see it. Till after you cut an end off or slice the insulation and look at all the green corrosion.
If they have the cheap bolt on battery terminals THROW them away, they are junk.
New cables.
At the very least clean the connections. ALL the connections. Tight. No grease, oil, rust, paint,
Another thing to do is move the ground [your car is positive ground] connection from the motor to one of the starter bolts.
The starter needs all the current it can get.
Do the obvious things first before you go off trying more elaborate fixes.
My 55 did the same thing.
Professionally rebuilt starter didn't fix it.
New solenoid didn't fix it.
NEW CABLES.
Sucker starts like its on 12 volts. Hot or cold.

[nvonada]

You can do a quick spot-check by running a jumper cable directly from the negative terminal to the lug on the starter. If it cranks well then it is a wiring or switch issue. Another good check is to use a voltmeter to check the voltage while cranking. If the voltage at the battery drops way low your battery is not doing well. If the voltage at the starter is a lot lower than the voltage at the battery you have issues in the wiring. NAPA has a large selection of pre-made heavy cables.

6V systems are just fine and work well but is a slave to Ohms law. That law says that V=IR where V is the voltage, I is the current, and R is the resistance. Voltage is limited by the battery. Current (I) is what makes the starter spin but as R (resistance) goes up the current has to drop since the voltage is fixed. More voltage tolerates more resistance. That is why back when dinosaurs roamed the earth lot of people installed 8V batteries. But that is a band-aid. The real fix is to maintain the wiring, keep the battery terminals clean, and remember it is positive ground!

Nathan

[Tom Bredehoft]

One more thought, my '53 had similar problems, I'd stop at a sation for gas, It might not start, cranked hard.

I took the starter to a repair place, they replaced the bushing and the worn armature, it had been dragging on the windings, slowing itself down.

[Noxnabaker]

Since the car has troubles starting when it's warm you also might consider the ignition-coil.
Not that it'll slow down the turnings of the starter but I've had 6-volt cars that would start with just about a half turn reeeaaal slooow turn... no problem with hot coil then.

[Rocket442]

Check if battery is wet with acid as it could be arcing or grounding out.
Dont bother cleaning it if its leaking just get a new one its done.