Yamaha Gas Not Charging

[Prowlerguy1]

Originally Posted by pepperoni

I did a continuity check on the switch side after I sprayed with contact cleaner. Seems to be working now, nothing when the pedal is up, beep when pedal is pushed a little.

Awesome!! That will help a lot!!

Originally Posted by pepperoni

Is it OK to run one wire to all three of these spots or do you suggest running three separate wires. I guess my question is, how would you wire it ?

Thanks again for you time, knowledge and most of all ... patience !

Hey, no worries. You're doing all the hard work! I'm glad I can help.

SORRY, THIS IS A LONG POST!

I have been thinking about your situation while I've been working on my G8 cart today. I haven't had any luck today, but I think we can get you running...and charging.

THIS BEGINS THE LONG ANSWER!:lol:

Let's think about this for a minute. On a "normal" cart, battery power goes through the key switch, through the pedal switch and then to 5 components:
1. The coil pack;
2. The ignitor (or CDI, or TDI, or equiv);
3. The V/R;
4. The S/G excitation field coil;
5. The starter relay solenoid.

On your cart, you appear to have some type of a magneto ignition system that doesn't need to have battery power to run. Your "stop" button grounds the magneto output and shuts down the cart. So, that makes items #1 and #2 above - not applicable.

Now, Item #3 - the V/R. You say that the R/W on the V/R goes on/off with the key. I guess that's OK. Most carts, the V/R goes on/off with the pedal. Probably not a big deal and could be either way. I don't think it would harm the V/R to stay on all the time the key is on. It doesn't seem to have bothered it so far.

Item #4 - S/G excitation field coil. Right now we have that wired to the key. That's OK for testing, but I would not want mine to be wired that way. Two reasons come to mind quickly: 1 - drains the battery when the cart is not generating power and key is on; 2) - might have heating issues with current through the excitation coil constantly but no motion in the S/G. Most motors and generators cool their windings with fans mounted to the shaft. If there is current running through the coil all the time the key is on, but the S/G is not rotating, it "might" overheat the coil. I really don't know this for sure, but I'm being conservative here.

Item #5 - Starter Relay Solenoid. Right now, your "start" button sends power to the solenoid to start the cart. Once started, the magneto ignition keeps the engine running. When you release the "start" button, the start solenoid de-powers and the start relay opens. We've already discussed why this is not allowing the battery to charge.

I think we can send power to the starter solenoid from the pedal switch in addition to the power from the "start" switch - WITH ONE RESERVATION. We have to figure out if the ONLY thing powered by the "start" switch is the starter solenoid. I am pretty sure it probably is, but if it is not, then there might be a problem with this set-up backfeeding +12V power to some other component(s).

If you are only backfeeding the "start" switch, that's no big deal. But, if there is anything else that is on that Black/Blue wire, this might cause a problem. I just can't say for sure, because short of ripping into the whole electrical system, there isn't a way to find out where else that Black/Blue wire goes.

There is one other consideration to powering the starter solenoid from two places (the "start" switch and the pedal switch). Namely, the pedal will start the cart on the first use. You could still start the engine with the "start" switch like you have been doing. However, if you get in, turn on the key and hit the pedal, that will also start the cart the first time (you step on the pedal). When you let off the pedal, the cart should continue to run. Once the engine is running, you can step on (and release) the pedal and you want. All it will do is cycle the start relay open and closed.

Also, you need to be sure that the pedal switch is fed from the brown wire of the key switch. You don't want "always on" battery power going straight to the pedal switch. You will still have to shut the cart down with the "stop" switch.

The whole reason, of course, that you WANT the starter solenoid powered from the pedal switch is that whenever you're driving the cart, the pedal will be down, the engine will be running above idle speed, and the pedal switch will be closing the starter relay and allowing the battery to charge.

SO, NOW THE SHORT ANSWER:

Yes, I would pretty much do as you mentioned. I'd run a wire from the output of the pedal switch to each of:

1.) The V/R power - Remove the current R/W wire and tie in the new wire from the pedal switch.

2.) S/G excitation coil power - Connect to the little red wire going into S/G. Remove the current wire coming from the brown wire at the key switch.

3.) starter relay solenoid power - Connect where the Black/Blue becomes Red/White wire and leave the Black/Blue wire there. Just add the new wire to the Red/White wire as well.

I have attached a drawing. It's a little crude, but you should get the idea.

I think this will work for you. Please let me know what you think.

R/Todd

[cgtech]

Aw now i realize where i got lost on this.......the "starter button"! I dont know if it was original equipment (i suspect not), i know the US market carts never had that.... I agree with the above suggestions to possibly fix this. Btw, the "blue & black wires" i know of (at front bottom of engine) are "closed/connected" by the small relay to ground out the (magneto powered) coil to kill spark when pedal is not pressed on US market carts.

[pepperoni]

Originally Posted by cgtech

Aw now i realize where i got lost on this.......the "starter button"! I dont know if it was original equipment (i suspect not), i know the US market carts never had that.... I agree with the above suggestions to possibly fix this. Btw, the "blue & black wires" i know of (at front bottom of engine) are "closed/connected" by the small relay to ground out the (magneto powered) coil to kill spark when pedal is not pressed on US market carts.

Hello cgtech ... you are correct, it has a button to start it and a button to turn it off, not original equipment. I thank you for your help, I hope this thread comes in useful for other cart owners.

[pepperoni]

Prowlerguy1 ...

I did the three splices and cut the wires that you had in the diagram. I'm very happy to say that the cart seems to be working perfectly.

The foot starter works. As you are driving along you can hear the solenoid kick as you press on the accelerator. My voltmeter quit working yesterday, but we took a LONG ride last night with the headlights on and it started very powerfully this morning. Before, if you had the headlights on for any amount of time it needed to be charged.

I thank you again for your knowledge and patience. I hope this thread will be of help to other cart owners. I'll PM you in a couple days.

Cheers ... Ron

[Prowlerguy1]

Originally Posted by pepperoni

Prowlerguy1 ...

I'm very happy to say that the cart seems to be working perfectly.

The foot starter works. As you are driving along you can hear the solenoid kick as you press on the accelerator.

I thank you again for your knowledge and patience. I hope this thread will be of help to other cart owners. I'll PM you in a couple days.

Cheers ... Ron

THAT'S SUPER, RON!

I'm really happy that I could help you solve your problem. Nice job troubleshooting and fixing.

Now you can enjoy the cart and not have to worry about charging it all the time.

Regards,
Todd

[pepperoni]

Prowlerguy1 ...

It has been a month now since you repaired the charging system on our cart. It has been working very well, so nice not to have to drag the charger out every few days. I went back over the connections to solder, put shrink tubing and run the new wires with the factory wiring.

Thanks again for your knowledge and patience,

Merry Christmas

Pepperoni

[mike.houston]

we have a Yamaha 1994 gas cart and its not charging the battery back.how can we test the output of the generator to verify its good....
???

[Greek Wizard]

I have the same issue as Pepperoni I think, so I will be coming back to this thread to follow the advice Prowlerguy1 has given and I hope to have same result (I have changed everything possible, S/G, battery, V/R, the works)