1946 Willy's jeep Starter question

[wtd]

I'm working on a friends 1946 Willy's jeep that has a Dauntless 225 engine in it. It currently is not running because he was attempting to start it and it cranked several times and then quit and then wouldn't crank.

I discovered a blown fuse and after replacing the fuse, it would then crank but not start. We discovered that the positive battery cable was getting super-hot to the point that the positive cable end was starting to melt. The battery cable ends were questionable, so I replaced them and discovered that the post down on the starter that the positive cable was attached to, was loose. I tightened that post up and the cable no longer got hot when cranking.

While trying to figure out why it wouldn't start, I discovered that the S post on the starter solenoid had a constant ground with the ignition off and was in turn pulling the voltage down on the ignition switch ACC and IGN studs which in turn was only allowing about 9 volts to the HEI distributor which is attached to the IGN post. I also discovered that I have no spark to the plug wires.

I know that I should not have a constant ground on the S post of the starter. My question about the starter is this. Should the metal tab that connects to the starter solenoid from the starter motor case also have a constant ground on it? I removed the starter and removed the solenoid from in and when I grounded the case of the motor, that metal tab coming out of the case that bolts to the solenoid had a constant ground on it even with the solenoid removed.

I'm thinking that the positive cable getting burning hot caused some internal damage to the solenoid and possibly the starter motor even though the starter will still work.

Here is a picture of a similar starter and the metal tab I'm talking about that is coming out of the starter motor case is in the 3 o'clock position on the solenoid. It's the fourth picture down in this link.
https://www.ebay.com/itm/386283220468

Thanks for any input.

 

[The_Jeff]

That's not the ground, that's the wire that goes into the main motor to make it go! There should be some continuity between it and ground as it takes power to make the starter spin; ohms law says something that takes a ton of amps will have low, but not zero, resistance.

If you have the starter sitting on a bench next to a battery and jumper cables, you can mock up to see if it works. Negative to ground, positive to the big lug. Jump the small lug to the big one and she'll spin up... and try to jump off the table, LOL.

Incidentally the extra posts on your fender solenoid are for points distributors, so they can get full battery power during cranking. You don't want to feed the HEI the 9 volts through a ballast resistor/ resistor wire ignition feed; rewire for a full +12v if you're on a 12 V system (which is probably not OE.) Discard/ ignore the special terminal that also gives full power.

 

[wtd]

That's not the ground, that's the wire that goes into the main motor to make it go! There should be some continuity between it and ground as it takes power to make the starter spin; ohms law says something that takes a ton of amps will have low, but not zero, resistance.

If you have the starter sitting on a bench next to a battery and jumper cables, you can mock up to see if it works. Negative to ground, positive to the big lug. Jump the small lug to the big one and she'll spin up... and try to jump off the table, LOL.

I was talking to someone who told me the same thing so I'm going to assume that tab should not be grounded like it is.

The other day with the starter still in the vehicle and the S wire still connected to the starter solenoid and the S stud on the ignition switch, I tested the voltage at the IGN and ACC post on the ignition switch and was getting about 11.3 volts. When I removed the S wire from the ignition switch, voltage at the IGN and ACC posts jumped up to battery voltage. The BATT post of the ignition switch also had battery voltage. That definitely points to a starter issue either the motor or the solenoid.

 

[Eddie Hudson]

I'm not sure but I think the 1946 Willys 4 cylinder engine used a 6 volt positive ground system. If it does, you're going to get hot cables, burnt points and eventually blown fuses using a 12v battery.

 

[K-Man]

I'm not sure but I think the 1946 Willys 4 cylinder engine used a 6 volt positive ground system. If it does, you're going to get hot cables, burnt points and eventually blown fuses using a 12v battery.

This. Everything back then was 6 volt, unless converted to 12. The big switch to 12 volt did not start with most vehicles and tractors until the mid–1950s models, and some holdouts such as VW Beetles stayed with 6–volt systems well into the 1960s.

 

[mk378]

You could temporarily feed the distributor from another battery to test the ignition itself and rule out everything related to the car wiring.

Starter may be a conversion 12 volt unit if the system has been converted properly.

The HEI should still fire at 9 volts though. As others said the HEI should be fed directly from the ignition switch with only a fuse in between.

 

[The_Jeff]

Yeah if it came from the factory positive ground the starter would have to be changed-- no way to isolate it electrically, and it would spin backwards. Assume shenanigans within the starter case.

 

[mk378]

Actually a starter will spin the right way regardless of battery polarity. The field magnets are also electric, so (unlike a permanent magnet motor) their field reverses and compensates for the opposite polarity in the armature.

Of course the solid-state ignition requires negative ground as designed. Make sure the negative of the battery is grounded.

 

[wtd]

I'm not sure but I think the 1946 Willys 4 cylinder engine used a 6 volt positive ground system. If it does, you're going to get hot cables, burnt points and eventually blown fuses using a 12v battery.

This Willys doesn't have the original engine in it and there are no 6 volt wiring hooked up. My friend has had this jeep for 20 years and it ran fine until recently so the only new issues were the loose battery post on the starter causing the positive cable to get very hot when cranking and probably it was hot while running. I only first saw that there was an issue when I saw smoke coming from the positive battery terminal when he was cranking it and saw that the terminal was starting to melt.

 

[Eddie Hudson]

I missed the HEI part of the OP. The starters job is to crank the engine, which yours does. You should be checking for SPARK & FUEL.

 

[wtd]

You could temporarily feed the distributor from another battery to test the ignition itself and rule out everything related to the car wiring.

Starter may be a conversion 12 volt unit if the system has been converted properly.

The HEI should still fire at 9 volts though. As others said the HEI should be fed directly from the ignition switch with only a fuse in between.

The starter is a standard Delco Remy starter used on older GM engines. The Dauntless 225 engine that is in it is a mid 60's one that has had a GM HEI distributor added to it at some point. It also is using an electric fuel pump which they have tied into the same power wiring as the HEI unit which goes back to the IGN post of the ignition switch. This vehicle has run fine until recently for the entire 20 years that he has owned it.

When I first looked at the jeep after it quit cranking when he was trying to start it, with the ignition on, I had ground at the HEI power wire and the power wire for the electric fuel pump. I knew that was not correct, so something seemed shorted out. My friend replaced the ignition switch thinking it was the problem, but it didn't fix anything. Only after I removed the S wire from the ignition switch did I get voltage to the HEI and fuel pump connectors and had the correct voltage at the ACC and IGN posts of the ignition switch.

 

[wtd]

I missed the HEI part of the OP. The starters job is to crank the engine, which yours does. You should be checking for SPARK & FUEL.

It currently doesn't have spark to the plug wires and is why it currently won't start and the electric fuel pump does work and the carb is getting fuel but my issue is that with the starter hooked up, it is pulling the voltage down to the HEI to 9 volts. We replaced the HEI module and the coil but it was before we discovered the hot battery post issue and the ground on the HEI wire so the new parts may have been damaged and why there is no spark.
Some people say that 9 volts is not enough to have the HEI run and others say it is so I don't know. I'm just trying to verify that I should not have a constant ground on the S post of the starter solenoid with the ignition switch off. I tested the S post of the starter in my 92 Cavalier in the same situation and there is nothing on that post with the ignition off.

 

[The_Jeff]

Probably time to hook up an inline ammeter inside your various suspect circuits. Something that will drag the ignition positive voltage down to 9V will be a substantial load. You'd also be able to identify a given load by number of amps drawn and chase it to its logical conclusion.

As for the S terminal, what's your thesis for its existence? If you can't think of one, try going without. Minimize to get a running jeep then add circuits from there.

They "used" to use the terminal to jumper around a ballast resistor for points ignitions, which is an obsolete item in your example, so I'd be comfortable going without.

You should also question what changed, I feel you have a bad ground somewhere else entirely and electricity is taking a new path. Measure for voltage between any number of points that are supposed to be the same and see if you find any.

 

[wtd]

Probably time to hook up an inline ammeter inside your various suspect circuits. Something that will drag the ignition positive voltage down to 9V will be a substantial load. You'd also be able to identify a given load by number of amps drawn and chase it to its logical conclusion.

As for the S terminal, what's your thesis for its existence? If you can't think of one, try going without. Minimize to get a running jeep then add circuits from there.

They "used" to use the terminal to jumper around a ballast resistor for points ignitions, which is an obsolete item in your example, so I'd be comfortable going without.

You should also question what changed, I feel you have a bad ground somewhere else entirely and electricity is taking a new path. Measure for voltage between any number of points that are supposed to be the same and see if you find any.

The S terminal on the starter solenoid is the positive voltage to the solenoid when you turn the ignition key to start. All starters that I know of have this.

As I stated earlier in this thread, the S terminal has a constant ground on it with the vehicle at rest with nothing on. This was tested using my Power Probe which turned on the green light, activated the buzzer on the tool, and showed 0.0 volts on the screen. This in turn is pulling the voltage down at the ignition switch for the ACC and IGN posts to about 11.2 volts with the ignition switch turned to the ACC and IGN spots on the switch. With the switch off, the Power Probe shows the same things as it does down at the starter solenoid. The power for the HEI unit is from the IGN post of the ignition switch. When you crank the engine, the power to the HEI drops down even further to the 9 volts referenced above.

I believe that the loose battery stud on the starter solenoid caused some type of internal short in the starter motor itself because if you isolate the starter solenoid from the starter motor, you still get ground at the post coming out of the motor that connects to the solenoid and this is with the starter out of the vehicle but with the case grounded. I believe the excess heat generated by trying to start the vehicle which was making the entire cable from the battery positive post down to the starter solenoid super hot caused damage to the starter.

This entire issue started when my friend went to start the jeep. He was cranking it trying to get it to start and then it just quit cranking at all. He called me and I did some testing and with the ignition key on, I had ground at the fuel pump connector and at the HEI connector which is tied together on the same wire and goes back to the IGN post of the ignition switch. Obviously have a ground on the power wires will not allow those components to function. I found a blown fuse and replaced it and then the engine would crank again but I still had ground at those two connectors. I finally traced it back to having ground on the S post of the ignition switch which that wire goes down to the S post of the starter solenoid. Taking the S wire off the solenoid post restored the correct power to the posts on the ignition switch. During more testing, Is when I discovered that the positive battery cable was getting immediately hot when cranking and that is when I discovered the loose battery post on the starter solenoid. After I tightened that up, the cable no longer got hot when cranking. During this I also discovered that I had no spark to the plug wires. Until I can find a known good starter, I cannot diagnose the no spark issue

I don't know if having ground instead of power on the power wire to the HEI damaged the new ignition module and coil that we had previously installed or that 9 volts at the power wire while cranking is not enough to activate these components.