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Need help, to understand the wiring in my car. It is a RHD with no foot starter but a start button in the dash. In the 1940 Wiring Diagramm there is only one Cable to the Starter, nothing more. When you look at my plan, you can see four Cables. One from the batterie, one from "L2" to "A" of the Generator / Voltage Regulator, L3 to the Start Knob and one to the Amperemeter. So tell me, why the one to the Generator / Voltage Regulator
It worked, but I don't understand the function. I want to install a relay for starting. How do I wire it, do I need two relays?

Links to diagramm Pictures

Hi Andre. the wire from the relay to the generator A terminal will only work when the engine or generator is stopped.The idea is to prevent the starter operating when the engine is running.With a running engine the armature voltage will be above 6 volts and the relay will not work with that circuit. The relay needs a ground to complete the circuit which the armature becomes when it is stationary. This circuit is used on other GM cars but i rather use a ground connection than connect to the A terminal of the generator to simplify matters.

I agree with wannchev's explanation. The connection from L2 to A will make a ground for the starter relay through the armature only when the armature is not turning.

I also agree that it is simpler to make a direct ground for the relay. You could use a short piece of wire to connect that relay terminal to one of the small cap screws that is used for mounting the starter relay to the starter housing.

Ok, I understand, Thats interesting. So i could wire like my Example Picture?!

Hi Andre,

Thanks for the pictures. They really help.

My suggestion is to run a short jumper wire from L2 to the hex cap screw at the end of the green line on the right of your picture. You should connect the wire from 60 on the push button switch to L3.

The nut on the stud at the end of the other green line is actually the high amperage connection on the starter itself. It will get energy through the contacts in the relay when the relay closes when you push the button on the dash.

You should connect the positive battery cable to the bare stud on the relay. That is the stud on the right in your picture 153053. The heavy wire on the left stud connects to the starter windings.

Thank you very much for your Support. What do you think about my new wiring Diagramm?

Hi Andre. With your new diagram why do you want a relay to operate another relay? The start button can easily switch the existing relay.Its the same logic in play when you fit a headlight relay to operate the headlamps. If the wiring is the correct size you dont need a relay for the headlamps. The engineers at Delco who designed the starter had more brains than me.

Hallo Andre,

I am impressed with your capabilities to create the diagram and your attention to details.

I agree with wannchev. I am not sure I understand the purpose of the relay you have added between the starter push button and the standard relay that is mounted on top of the starter. The power from the starter switch to operate the standard relay is very low. My estimate is that at most you would need a 16 gauge wire. 18 gauge is probably adequate.

When you energize the standard relay on the starter the high current goes directly to the starter through that very short heavy wire.

Let's keep talking. We will get this figured out.

As a sample I had a modified circuit diagram of a Volvo Amazon. There the starter was controlled by a relay. But the Volvo has no start button either. I wasn't sure if this really makes sense and just drew it in. But it is not really necessary.

Some circuits, like the double secured parking light, are a prerequisite for the German TÃœV.
The Diagramm is edited with Paint

Hallo Andre,

I agree that you do not need the additional relay in the starting circuit. In many cars the relay for the starting motor is mounted remotely. It is not mounted on the starter like the Chevy. The advantage with the Chevy design is that you only need one heavy duty cable to carry the current to the starter.

With a remote relay you need a heavy cable from the battery to the relay and a heavy cable from the relay to the starter. I never understood why Ford used that design for so many years. The only advantage I could determine is that if the relay became defective it was much easier to replace because it was readily accessible on the inner fender.

I appreciate and understand the need to meet the prerequisite for TUV especially with respect to lighting.

I think you will be pleased with your final results.

Optimized. Any more Ideas, Corrections.Had forgotten the power for fan and parking light?

Andre, one last thing i forgot to mention. The holding coil on the existing solenoid and relay can crank down to about 3 volts on the battery, allowing for cranking with a flat battery. Your additional relay will also have to stay in with this low voltage.The Delco guys thought of this.

OK. But when i use no other relay, like my last Diagramm, than there is no Problem, right? By the Way, when you klick on the Wiring Diagramm that is openend in a new Windows, it gets bigger

Morning Andre. You are correct your wiring diagram is ok. As a comment which is neither here nor there the factory wiring diagrams are very simple probably to reduce costs and make it easier for maintenance. Chevrolet went to pains to explain the functions of electricity in the factory manual.The more wires you add the thicker the wiring harness becomes especially if you use the old type cloth wiring.If you use modern XLPE auto wire the wire insulation is much tougher and the wires dont take up so much room in a harness.

Hallo Andre,

I believe that this diagram is a working system.

Here are some observations to make sure I understand the operation correctly.
1) The electrical loads for the cigar lighter and horns will not show on the ammeter.
2) It might be easier and use less length of heavy wire (10 gauge) if you connect the power for the horn relays directly to the power connection on the starter relay.
3) It appears that you will use a separate grounding switch to activate the town and country horns. So you could energize both horns at the same time if you really wanted to get someone's attention!
4) The electric fuel pump will run whenever the ignition is on. Some people only use the electric fuel pump to help get the car started. They then turn it off and let the mechanical fuel pump keep the engine running. There are sometimes concerns that the electric fuel pump delivers more than the carburetor can handle.
5) It might be easier to connect the power wires for the fuel pump and blinker and accessories (diverse) fused circuits directly to X2 on the ignition switch.
6) You show only one on/off switch for one heater fan motor. My car has a 3 speed switch for the heater motor and another 3 speed switch for the defroster motor. It depends upon the design of the heater.
7) You have front fog lights but no rear fog light. My experience with cars in Europe is that there is often a separate rear red light or one of the taillights burns brighter when the front fog lights are on. That requirement might no apply in your situation.

Great work!!!

Hello Rusty, very helpfull. Thanks
1) That was the original wiring. Is that not okay? Don´t know, what have to connect to the ammeter?!
2) will check this
3)Here you can follow the Post about my Horn Wiring
4) The Pump is a 6 Volt interrupter type petrol pump and not installed yet, I only have one in my spare box and will be prepared for Insatallation. The mechanical one works good and before Motor start i make some gas in it with a hand Pump.
But otherwise the E-Pump must be wired with a special relay and the Coil, so when the Motor not starts between the first Seconds the Pump does not work any more. In Case of an Accident she does not work any longer, when the engine is not running.
5) same as 2)
6) Harrisson Fan ( one Motor/ one Cable) and a Rotary Rheostat Heater Switch from Cot40s
7) You are right, but it is not necessary for Classic Cars. By the way, the Fog lamps are not installed too. But I do a new Harness and will be prepared for the Future.

Hallo Andre,

Great answers. Thanks for the confirmation and details.

I agree that it is not necessary to connect the cigar lighter and horns across the ammeter. Those are not continuous load like the lights and fan motor.

That is an interesting fuel pump. It is variable displacement by controlling the frequency/speed.

I remember the extended discussion abut the horn wiring. What you have will work just fine.

Best wishes as you start building the wiring harness.

Andre
I install LPG as a fuel, as part of the safety control I have to fit a special switch (tachometric relay) that would be ideal for your application. It connects to battery +, coil -, LPG tap (fuel pump in your situation), you would connect it to only allow power to the pump when there is pulsing power at the coil. I think there are 6v versions but would have to check. I have 1 on my dual fuel (petrol/LPG) daily driver.
Tony

Hello Tony, that's exactly what I mean. But it's hard to find it in 6Volt. Alternative I could install a crash Sensor who cuts the power to the pump. But at the moment only want to install the needed wire for the Future

If you decide to go that route, some of those switches are better than others. F**d used them a lot, and they are generally found at the left rear of the vehicle inside the trunk on cars, or on the cab side of the firewall near the middle in trucks. I would suggest finding one from about an 86-87-88 BroncoII or Ranger. Those smaller switches were reliable and false tripped less than the earlier, larger switch.

Ok, will see if I can get one here in Germany

This is interesting! Goggle "Ford Inertia Switch".

Another idea is to put a electric switch in the oil gallery that needs oil pressure to turn on. Or a standard oil pressure switch controls a relay that turns off when no oil pressure. There can be a manual over ride system built in if required.
Tony

This week I wired the engine to try a first start, unfortunately the engine doesn't move at all. The starter only makes a short click noise. After that everything is completely dead. After a certain time I can try again, but again only click. Engine doesn't rotate, Starter doesn't rotate. I wired it according to the picture. FGB is voltage regulator, ZÜ ignition lock, Anlasser = starter
What’s wrong? Battery has 6,3 Volt, same at start button

Surprise, after the, feeled, 20th Try, the Engine cranks?!