Tuesday, November 26, 2019

Wiring a Zongen ATV 250CC

I have had this Chinese Zongshen 250CC quad for  six or seven years now.  In those years, I have re-welded the axial frame, tried to fix the carb many times, but it never really was reliable.  In the past year, getting it started was impossible and recently could not even get the starter to crank.

So I decided to rebuild it.

Parts:

Carburetor Replacement:
This was a one for one swap.  It fit perfectly.  The only difference is the choke assembly.  This has a handle that clicks, where I just have a choke cable to adjust on the old version. I think I can just swap out the assembly and be good to go.  I find that if I take off the seat, it is very easy to adjust the choke.

Wiring Harness:
The harness came with no connection diagram or instructions and was a bit differen. It also had some different connectors for the lights and Stator.  Was planning on just reconnecting the old Stator but since the connections were different, decided to change that out.  Details on Stator replacement below. Here is a diagram I made based on my current connections.  For the lights, I reused the light connectors from the old harness and connected the blue, white and green wires in the front of the new harness.

Replacing the Stator:
This was not an easy task and took me a few hours. I could not find any good instructions so mostly figured this out from looking at many other types of replacement.

Step 1 - Remove the Eight bolts around the Stator compartment. Starting with the top center bolt and working counter clockwise (to the left), remove the bolts.  There are different sizes so keep them in order. And then repeat from the top when putting them back in. You may have to remove you stand and gear shift as well.

Step 2: On the same side - remove the three bolts on the starter casing.  Remove the casing - be careful to note the gear, it may fall out.  The larger gear is on top or the closest to the outside.

Step 3 - Remove the one bolt on the top left in the starter casing where the gear sticks through. On the other side of the ATV, remove the long screw bolts holding the starter to the casing from the .

Step 4 - Using a small tack hammer - lightly tap on the Stator housing to dislodge it and break the seal.  You maybe able to just pull it off without tapping, but mine was stuck on there.

Step 5 - Remove the old Stator.  Cut the cable - remove the three bolts on the Stator.  Remove the two screws holding in the pulse sensor.  This was difficult as they would not come out and I was afraid of stripping the Philips screws.   I soaked them in bolt release lubricant for several hours.  I eventually  had to heat the outside of the casing with a torch before they would break free.  Use anti-seize compound on the bolts before putting them back in.

Step 6 - Install new Stator - Note the color and the position of the wires to the connector.  I marked them with a Sharpe.
Using a small paper clip or piece of hard wire, slide it up in to the connector to push the slide pin down.  This will release the pin, and allow you to remove the wire from the connector.  After all the wires are removed from the connector, slide the wires from the inside of the case out through the cable hole.  Re-seat the runner grommet and the three bolts to the Stator, Put the anti-seize compound on the pulse sensor bolts and install them.  Reset the wires back in to the connector as noted.

Re-install the casing in the reverse order.  Pay special attention to how the wires are routed up from the engine.  Not getting them tucked in good and hidden will prevent the casing covers from aligning correctly.

Still no Start????
After all this and getting the harness connected and all the parts installed, the bike still would not start.  I did not have a spark - why?????    There are two gotchas here!

1) Mid way in the harness, you will find two wires that have matching barrel connectors, join them as this connects 12 volts to your switch.  See the wiring diagram.

2) The kill switch on the new multi-switch is a slider. To kill the engine, you slide the switch to either side.  However, this is a locking slide, you must push in the button to release the kill.  After several hours of trouble shooting this and finding this video on how to diagnose the Stator and CDI, I figured this out.  It came down to the one pin on the CDI being grounded so know that was shorted some where.  I took the harness apart and found the joined wire going back to the multi-switch and by accident, pushed the button in and noticed the change in ohms on the CDI.  After that - started right up!

Connecting the Lights:
Since the connectors on the front are different.  I used the old light connectors and soldered them to the Blue/White connector, and then use the green wire for ground.  Most the other wires on the front or spare connectors as noted in the diagram.  I think some could be used for the back break light that I do not have connected - but the running light works.

Hope this helps someone else - and happy trails!


tim

25 comments:

  1. Hey, thanks for this blog. I'm trying to get a non-running Chinese 250cc bike going. Also decided to buy a whole new wiring harness and parts. Still working through it, but this was really useful!

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  2. any ideas on why my wires are getting hot . the original ones melted the second set melted as well and the one I have new gets real hot too

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  3. I'm trying to wire mine up too. but ever time I start it the wires start to over heat any ideas

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    Replies
    1. This means something is drawing to much current. Try using an ohm meter to see if any of the positive wires have resistance or shorted to ground. Also if it is electric start, the starter or solenoid might be drawing to much current. If they are getting hot and melting after it's been running a while, then you need larger gage (lower wire number) set of wires. You best bet is to use an ohm meter and measure the resistances, voltage across each element in the circuits. good luck...

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    2. Hey Tim, I found this blog post on the atv connection forum. I'm struggling to figure out some extra wires on the new harness I purchased and hoped you could assist. I sent a reply to you there with pictures. if emailing is easier, the best one for me is lazrslong@comcast.net.

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    3. Hi lazrslong, pleas post your pictures as not sure which ones here you are referring too? If you expand the wireharness pic in the post, that shows various connections with the harness and stator I purchased. Your harness maybe different.

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    4. Here are some pics of my old wire harness - maybe that will help some folks. I kept it for spare parts just in case and found it in the workbench drawer this weekend.

      https://photos.app.goo.gl/Vqg56jXtzgXLW6c47

      https://photos.app.goo.gl/P2xzNuzz8htPrVRm6

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  4. My motor turns over really hard I don't know why

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  5. My motor turns over hard don't know why

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  6. All new Chinese 250cc motor wiring Harness . What I'm missing and what the hell are the wires coming out the motor???

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    1. Hi Daniel - the wire coming from the engine at the bottom by the chain/gear shift lever are your strator wires. They plug in to the strator plug as noted in the picture. This is what charges the battery.

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  7. Im currently repining the same harness and need help. What wires go where from the harness to the LH multi switch. And what wires/colors did you connect with those barrel connectors.

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  8. My left hand switch had connectors that matched and connected on the front of the wire harness. For the lights, I used a volt meter to test which barrel connect was for Hi.Low beams. Look at the picture of the wire harness and enlarge it. That may help. My bike is in storage so can not look at the wires. Good luck!

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    Replies
    1. Thank you i havent had any luck today. Still no spark.starter spinning but not getting spark im loosing my mind haha thank u tho

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    2. Try pushing in on the kill switch to reset that. On mine you can push right or left but you have to push it in to get spark.

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  9. Hi. I bought a wiring harness from Amazon. The loom wires (5 colors solid green solid yellow solid white and blue/white stripe and red/black) going to the stator. The stator has ( red/black, blue/white, solid yellow, solid pink and green/white. Which colors go with each other. Thank

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    Replies
    1. Hi Zaf, Unfortunately it depends on the wire harness and the manufacturer you bought it from. Mine came with a stator included with connectors already installed so it was just a matter of matching the connectors. I would ohm out the wires to switches, lights, and power, then what is left try to match to the stator wires. Sorry I can't help you more. Contact the manufacturer thought amazon, they may send you a wiring diagram. Good luck!

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    2. Hey Tim, I also have a 250cc atv and curretnly have no spark so i decided to order a whole new harnesss because I cant deal with tryinhg to fix the old one as it was a mess. As I am doing so I realized that the I have the same wiring harness you had ordered which has different wires going into the side by the starter and stator assembly. I have 3 yellow wires, blue/white, green and a batch of other wires such as red with yellow stripe, solid blue, white etc. But the problem is i dont know how you used an 8 coil stator in your 250cc atv. My 250cc atv has a 12 coil stator in it at the moment.

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    3. The wire harness I ordered came with a new Stator that had plugs to connect. If you still have your old harness, try to compare to how that was connected. Next time I am out at the storage place, I will try to remember to take a close up picture of this and post. Good luck and let us know how things proceed.

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  10. I picked up a magician 250cc it's a 167fmm engine, carbureted I bought it without the stator so I bought a new one. It has five wires coming out that includes the pulse
    blue and white
    Yellow
    Pink
    Red/blk
    Green/white
    Cdi is a 6 pin. The wire harness to the stator has two yellow one green and then the blue and white. What are the two yellows

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    1. HI Jason, not sure which wire does what. My new harness came with the stator and connector. Here is a pic of my old stator wires. Maybe that will help. Good luck. https://photos.app.goo.gl/myLeAgRq9so2XXMK7

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  11. Any help would be greatly appreciated my email address is jasoncrowley38@gmail.com I'm not sure if I'll get a message notification if somebody replies to this form. Thank you guys

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