Engine/ wiring harness help in my version of a "hybrid"

[Strike37G]

OK gang, first post so don't bust me up too bad. I am so out of my element here because I usually wrench Jeeps and an intermittent Charger.

I am taking a 250cc Zongshen engine and grafting it into a 2002 Yamaha Blaster. After modding mounts, carb, intake etc. I have ran into the problem of the engine harness to wiring harness. Both have 5 wires for the mag but the colors don't match. anyone have any experience with bridging the gap between the two? The first picture also has a 6 pin connector that I have no idea about. The second and third pictures are the loose engine wires and wiring harness with the connector. The whole project is sitting at about 95% and I'm ready to finish it. Any input would be greatly appreciated!

 

[Curtis Underwood]

Frst and foremost. You will need the wiring diagrams for 250cc Zongshen engine and the 2002 Yamaha Blaster. Wiring on the engine itself has:
1. The stator/altenator wires that will connect to the your regulator/rectifier on your ATV.

2. The engine may also have a neutral safety switch wires, oil pressure switch wires and or temperature switch wires. It depends on the engine to what wiring it has.
So unless you are good at identifying which wire does what. You will have to have the engine and ATV wiring diagrams. Then you if you are not real familar with electrical wiring, you should have someone that is do the connections.

Edited May 29, 2022 by Curtis Underwood

[Strike37G]

Nothing from the Yamaha harness is in play. Its literally a new harness. The wiring "diagram" is really crude and didn't show where each of the stator wires went. im going out on a whim the 6 pin plug coming from the engine is a neutral light.

[Curtis Underwood]

Does the engine have more than the 6 wires coming from it?
The engine stator usually has three wires that goes to the rectifier/regulator, one or two wires from the ignition sensor (depending on if the sensor used ground or not), and a ground wire.
The neutral switch is usually only one wire unless it has a shift indicator system, that gives which gear it is in then it might have a 6 wire connector.
Then on most engines you have a coil with two wires running back to the CDI.
Engines usually have either 9 wires to 13 wires coming from the engine going to the atv body.
Engines on early model machines have:
1. 2 coil wires one that leads from the coil to the ignition/stop switches and the other to the CDI.
2. 1 neutral safety wire that prevents the starter engaging unless the switch is closed.
3. 3 stator wires that got to the rectifier.
4. 1 ground wire from stator to body ground on atv.
5.  2 sensor wires that got to the CDI unit.

Engines on later model machines depends on the type electronic display if it has any certian wire:
1. 2 coil wires one that leads from the coil to the ignition/stop switches and the other to the CDI.
2. 1 neutral safety wire that prevents the starter engaging
3. 3 stator wires that got to the rectifier.
4. 1 ground wire from stator to body ground on atv.
5.  2 sensor wires that go to the CDI unit.
6.  6 wires from the shift switch (which includes neutral safety)
7.  1 wire from the oil pressure switch (optional)
8.  1 wire from the engine temperature switch (optional)

So you see how complex it can get. If you can not get a print that is color coded for your engine and one for you ATV wiring harness then you will need to trace each wire on the engine  and on the ATV harness to see what it goes to then hook it up to the corrosponding wire on the ATV.
There is no easy solution without the prints.

 

[Strike37G]

yeah its 5 loose wires from the engine to a 5 wire connector on the harness. I will research more from the manufacturer of the engine and see what the 5 wires go to then back track. might have to skin the harness and trace with a MK1 eyeball and check continuity.

[Strike37G]

Latest update. Got the Blaster to fire and run a few times then all of a sudden no spark. Changed CDI, rectifier, even the coil. Still no spark. Went through entire harness and beefed up the connection points. reinstalled no spark but I bumped the connector to the CDI got a slight "bump". Found out it was a bad connector. Swapped in a new one and voila! Starts, run and is good to go!

[Curtis Underwood]

Glad you got it going. Have fun.

[Ajmboy]

That's pretty cool! Nice job 👍

[Strike37G]

56 minutes ago, Curtis Underwood said:

Glad you got it going. Have fun.

Thanks!