Yerf dog GX150 GY6 electrical problem/who knows?

[FireMedicKK]

Hey everyone I am brand new to the site and am hopefully posting in the right section (if not my bad). Let me start off with I just purchased a used yerf dog gx150. It was running like crap, misfiring and bogging out at full throttle. I did a little tune up - new oil, gear oil, spark plug, ignition coil, air filter, fuel filter, gas tank and cleaned/respliced all the old wires. After all that it ran great, no misfires, good speed, and no complaints. After I did all that I had to put the all the wires back into the electrical box, which was very tight. I had to kind of force/finagle the wires in. After that the kart would not start. My kart I think is kind of "ghetto rigged". I cannot seem to get power to the "kill switch". I have 3 wires that come up to the steering wheel switches. Green, brown and black, with black being the common ground for both. The kill switch is powered by the green which I cannot seem to get power too. The brown wire is spliced by a green/yellow wire that has 12.6 Volts. I traced the green wire back to the 8 pin connection and from there to the regulator rectifier. It seems the only power I am getting is from the yellow/red wire coming into the regulator rectifier from the battery. I am not sure as to what wires are supposed to get power from the 8 pin or regulator rectifier? Didn't know if I somehow killed the regulator rectifier by trying to put the wires in the box? Is there a way to somehow test the regulator rectifier if it's bad? I have literally spent hours playing with all the connections and making sure nothing is loose and trying to retrace my steps. Am I missing something obvious? I have pics if that helps? Any help is greatly appreciated! I live in Lake Worth, FL incase any is local and wants to help a brother out. Thanks again!

[JERSEYDEVIL]

i am right across the state from you and have a shop in englewood fl.
you can call me if you'd like 941.286.6703. i'm in the shop from 3-8 on week days 9-5 weekends.

[FireMedicKK]

Originally Posted by JERSEYDEVIL

i am right across the state from you and have a shop in englewood fl.
you can call me if you'd like 941.286.6703. i'm in the shop from 3-8 on week days 9-5 weekends.

Thanks Jersey Devil, I'm sure I will be calling you tomorrow if that's cool. I hope it's something simple. I don't see how all the sudden I put the wires in the box and it doesn't work. Thanks again and have a good night

[xlint89]

Welcome to the sight.

If i remember correctly, there was something to do with the brake cylinder. Kind of like a safety switch?

Definitely check out the engine ground wire. It's an easy one to miss.

My engine to frame ground wire broke at the connector and wouldn't start.

[OLDKID]

Try working on it in a dark environment seriously . Had one that was arcing out to a rubber hose on carb , like you I had one that out of the box-run , in the box - no run . My solution , Silicone spray - LOTS OF IT . Also all three of my Yerf's coil connecters would try to arc , spit and sputter or not run at all no matter how clean and tight the connections were , once again Silicone . Learned this after running on jack stands in a darkened garage . Could see them - Electrical Gremlins like to show up in the dark . When you spot one blast it with Silicone to repel .

[SYCARMS]

The kill switch grounds out the ignition, both solid green and solid black are ground. Being it was running prior to installing cover I would go back and look for a loose connection in the box.

[GX150]

The Yerf has very simple control wiring. The start button connects the hot side of the starter solenoid to ground to crank the starter. The kill switch is wired to the CDI kill pin and will suppress the CDI any time you activate the switch and send a ground to the CDI.

I agree that you have loose wire or connection in your electrical box resulting in your problems and not at the controls at the steering wheel.

[FireMedicKK]

I'm going to try and upload a couple pics of what I think my problem is

[FireMedicKK]

Pic2

[FireMedicKK]

Pic3

[FireMedicKK]

Pic4

[FireMedicKK]

Originally Posted by GX150

The Yerf has very simple control wiring. The start button connects the hot side of the starter solenoid to ground to crank the starter. The kill switch is wired to the CDI kill pin and will suppress the CDI any time you activate the switch and send a ground to the CDI.

I agree that you have loose wire or connection in your electrical box resulting in your problems and not at the controls at the steering wheel.

What is the exact location of the CDI kill pin? Is my wiring right in the pics? I didn't change anything from when I got it. And thanks again everyone for your help

[SYCARMS]

It's a good thing you have no power at the green wire since it goes to ground. The wire next to it black with red trace should show ac voltage when engine is rotating.

[FireMedicKK]

How does the red junction get powered?

[FireMedicKK]

My kart is a little ghetto. Green and brown are hot.

[SYCARMS]

Well as per the wiring schematic green wire from cdi goes to on off switch in which other side of on off switch is black and goes to ground. When the switch is open you will have no spark, when switch is closed a ground is completed which allows current to flow. In all my years in automotive as well as off-road be it buggies, atv's or scooters solid green is ground. If as you say that green wire which goes to the on off switch was hot, then when the switch is made you would have a direct short since the other side of the switch goes to ground and wires would surely burn up.

[ckau]

A couple of pics that may help you out. I wouldn't trust the wiring colors though. I've seen different colors used but the schematic is correct.

[GX150]

Originally Posted by SYCARMS

Well as per the wiring schematic green wire from cdi goes to on off switch in which other side of on off switch is black and goes to ground. When the switch is open you will have no spark, when switch is closed a ground is completed which allows current to flow. In all my years in automotive as well as off-road be it buggies, atv's or scooters solid green is ground. If as you say that green wire which goes to the on off switch was hot, then when the switch is made you would have a direct short since the other side of the switch goes to ground and wires would surely burn up.

The Yerf is different. When the switch is closed, ground is applied to the CDI and suppresses coil output (no spark). When the switch is left open the CDI can drive the coil.

[GX150]

Originally Posted by FireMedicKK

I'm going to try and upload a couple pics of what I think my problem is

As I posted, power is directly coming from the stator. This means it is AC and only produced when the engine is spinning.

[FireMedicKK]

Just wanted to say thanks for everyones input, and a big shout out to Jerseydevil for spending like an hour on the phone walking me through everything. I believe I now have everything hooked up appropriately. My problem is now I'm hearing a whining from what I believe is the starter? I can feel the starter solenoid vibrating, and I believe the starter is making a whining noise. Does this mean my starter possibly went bad or my starter solenoid went bad? I'm going to try and upload a video

[FireMedicKK]

Also, is the AC ignition power the black/red wire that goes into the CDI?

[FireMedicKK]

Are both sides of the starter selenoid supposed to be hot? Because I am getting no volt reading on the red wire/right side of photo that runs to the stator?

[tkeagle]

I'd half to look at mine. But think both should be hot. Right side going to starter. Then
left side to CDI and runs up to steering wheel. But that's just best guess. Will need to look on mine.

[FireMedicKK]

Thanks again! I removed the starter and it is not getting power from the solenoid. I hook the starter up to the battery and it ran fine! Whenever I put the volt meter on the solenoid the power on the left side(battery) is at 12.6v and when I go to crank it, it'll drop to about 6v on the Left(battery) and right side which runs to the starter never even gets any volts? Is that a bad solenoid or am I shorting it out somehow? You guys know if I can just grab any starter solenoid from like Napa or autozone?

[SYCARMS]

The solenoid is normally open. Lead from battery to solenoid should read battery voltage. When start switch is made battery voltage is supplied to the grn/yel wire which closes the solenoid switch which than supplies battery voltage to the starter. You stated having voltage to batt side of solenoid but only 6v when start button is pressed. Do the same test but this time check voltage at battery. If voltage drops at battery when start switch is pressed, you have a bad battery. If voltage at batt is good when start button is pressed then check the lead wire from batt to solenoid for bad corrosion or breaks. If lead wire from batt to solenoid is good then make sure you are getting 12 volts from switch to solenoid. 6v is not enough voltage to close solenoid contacts. Not being there and just going from your post it sounds as if the battery is the culprit.

[FireMedicKK]

Originally Posted by SYCARMS

The solenoid is normally open. Lead from battery to solenoid should read battery voltage. When start switch is made battery voltage is supplied to the grn/yel wire which closes the solenoid switch which than supplies battery voltage to the starter. You stated having voltage to batt side of solenoid but only 6v when start button is pressed. Do the same test but this time check voltage at battery. If voltage drops at battery when start switch is pressed, you have a bad battery. If voltage at batt is good when start button is pressed then check the lead wire from batt to solenoid for bad corrosion or breaks. If lead wire from batt to solenoid is good then make sure you are getting 12 volts from switch to solenoid. 6v is not enough voltage to close solenoid contacts. Not being there and just going from your post it sounds as if the battery is the culprit.

The left side of solenoid is hot (from battery), green/yellow, and yellow/red are also hot (before switch is turned on). I don't have power to right side of solenoid until I turn the switch. When I turn on the switch to power the right side I only get about 3-4 volts and the left side of solenoid, green/yellow and yellow/red all drop down to about 3-4 volts. The starter is spinning the fan and the starter solenoid makes a clicking/sparking/whining noise. Battery is good mantaining 12.4v (using a car battery now). I am so close now. Fuel is being sucked by carb, I hear it attempting to turn over but that damn solenoid is making some weird noises

[FireMedicKK]

Just wanted to say thanks for everyone's input! The yerf dog is back in business.
Turns out I had a bad ground and miswired switch (my kart has
No yellow and green switch is flipped). Just put in a hi performance CDI today as well. I will post pics soon of the build. Thanks