Single direction installation diagram

[mervk]

First post and new member. Will try not to break any rules. I am a complete novice with auto electrics, as will be obvious from this post. For years my gas Yamaha starting/charging system has performed flawlessly, so I decided to duplicate that system on my Fairmont railway section car. Installed a brand new starter/generator, and wired it up with new voltage regulator to what I believe is similar to the wiring diagram for my cart. It starts the motor beautifully (no more crank handle!), however does not charge. Can someone please tell me where I am wrong in the wiring diagram below?

Note: As I do not need to start it backwards, I am using just one solenoid, and energising the solenoid during starting only by means of a starter button. I would however like it to charge when running in both directions.

I have not polarised the generator for two reasons. One, I assume that because the starter is working, there would be heaps of residual magnetism floating around in there, and two, I'm not sure if the regulator is an A or B circuit. Google tells me there is a different method for each. The regulator looks identical to that fitted to my cart.

Appreciate any help I may get from you guys. In the meantime I'll keep reading past posts. There is a wealth of info in this forum. Cheers. Merv.

[meimk]

The starter generator would need to be powered all the time the engine is running. What you have would work if: 1) the solenoid was a continuous duty type and 2) you hold that starter push button the entire time the engine is running.

[mervk]

Easy to do, I'll simply remove the starter button. However tried holding the button in while running, and appeared to make no difference. The solenoid is continuous duty.

Being a new unit, should it need to be polarised, even though the starter part is working? And is the Yamaha regulater A circuit or B circuit? Or better still, how do I polarise it?

Cheers

[mervk]

Something I don't understand. To add an idiot light I believe I would take it from the switch to the D+ which has the red generator wire. Bulb would be positive from switch switch and negative from red wire. When it starts to charge the positive from D+ would cancel the positive from the switch and the light would go out. Am I right with this? If so then my diagram showing positive from the switch to the D+ must be wrong. The light would never come on.

[sho305]

If you wire it like a GC the voltage regulator powers up the field wires, the small wires in the side of the gen though I think one is power and one is ground, and that makes it charge. The charge comes out the cables to the battery through the constant duty solenoid. Just put a switch on it, not momentary, and on is run off is off. You should see 13.5v on that battery when running that indicates charge, though a gen does not charge much at low speed you need about 2K rpm in a cart to see a good charge at 13.5 or more if cold or low battery, it varies. You should be able to test if the VR is asking for charge by powering the small wire. Make sure the VR has proper wiring it needs ground too in order to know voltage of battery.

[mervk]

Thanks for the help. If the solenoid has to be energized all the time then it appears I will not be able to have it charge in reverse? I will need to keep the charging circuit separate from the ignition circuit.

How would I wire a charge indicator light into the circuit?

Cheers Merv

[sho305]

Originally Posted by mervk

Thanks for the help. If the solenoid has to be energized all the time then it appears I will not be able to have it charge in reverse? I will need to keep the charging circuit separate from the ignition circuit.

How would I wire a charge indicator light into the circuit?

Cheers Merv

I don't think you have to worry about that, carts don't. Charge indicator, I don't know maybe power from the field wire or put a voltage gauge on it.

[mervk]

I'll slip an amp meter into the circuit for reassurance the belt is not slipping or other problem. Would really like an idiot light though.

The info I've gleaned from this and other posts has almost convinced me to go the whole hog and duplicate the Yamaha setup, with both solenoids. I bought two initially with this in mind. This motor runs with a trembler coil ignition, so I can easily isolate the ignition circuit from the charging circuit. A three way switch where forward would power up the trembler as well as the start solenoid. This would start then charge in forward direction.

The switch in rearward position would only power the trembler coil, and I would need to crank the engine in reverse. The starter/generator would be spinning backwards, however would not be powered. Would this cause damage?

Guess this will be my initial plan - get it starting and charging in forward, and manually start in reverse with S/G freewheeling. And then I'll look at going the full monty with the second solenoid.

Thanks Guys for the help. If anything else comes to mind to further my education, please post it for me to read. I appreciate all help.

And if anyone knows how to get an idiot light working, I'll be grateful. Cheers.

[sho305]

Running backwards you are looking at a G1 setup, check out the wiring diagram for one of those. IIRC it reverses polarity for the s/g. I don't recall what if anything the charge system does. The G1 spends relatively little time in reverse of course, so even if it did not work on a G1 it would not matter. I have never tested one, I don't know if it does or not. I know a G1 goes just as fast in reverse until you advance the timing, then it goes faster in forward than reverse lol.

[mervk]

Ok! Now I'm getting serious! Removed the starter button so solenoid is engaged full time, but still no charge.

Removed the green wire from DF terminal of regulator, and grounded it. Expected to see 16 to 20 volts on the voltmeter, but no change. Did notice though that when green wire was replaced on DF terminal, the battery showed less v, or more loaded, which is the opposite to what should happen if it's charging.

So, on a whim, and because it appeared to be backwards, we reversed the red and green wires, putting red to the DF and green to the D+ on the vol. reg.

And it charged! Showed around 12.7 volts at the battery, where previous it was just 11.9 or 12v. And it showed a charge for several minutes before deciding to throw the towel in again.

Swapped the red and green back to where they are supposed to be and draw on battery increased again.

What's going on? Hope someone can help, as I'm full out of ideas. As a side note, the new 'continuous duty' solenoid gets very hot, and draws around 2.4 amps to keep energised.

All suggestions will be carried out to the full. If you have any idea at all, please reply. Cheers. Merv.

edit: forgot to mention I read somewhere there should be 5 ohms across the red and green wires on the gen. Mine has 5.5, so all should be ok with it?

edit2: have read in 2 other posts that to test gen, remove the green wire from the GEN. and earth. This means we are earthing the DF terminal on the voltage reg, and the green wire from the gen. is now connected to nothing? Is this right?