Electrical System Help

[pcs800]

I have a 2 stroke chaparral motor in my project 8x8, I am going to (hopefully) run headlights, tail lights, dome light and wiper motor. My question is, do i run these straight off the battery or connected to the voltage regulator?

[Bazooo guy]

I would run a #14 wire from the battery to a 15 amp fuse and feed the switches for lights.
Run a second fused wire to the wiper motor switch...it will be higher current so size the fuse/wire to the motor you use.

[JohnF]

Battery.

[Don]

The older two-strokes are notorious for poor charging systems and the Chaps are no exception. The charge wires from the engine should run through the rectifier/regulator to the battery and then any accessories wired in from the battery through fuses. If you run very much load on the system at all, you may find that the battery goes flat on you.

[pcs800]

re

Don (or anyone) do you know which wires are the "charging wires"? We found one that puts out power but the other 3 don't seem to do anything. The one putting out power reads an extreme high voltage AC

[hydromike]

I'm guessing you have two yellow wires (or a solid yellow and a yellow/black) a brown, and a black/white wire. On most machines I've worked with, the yellow/yellow black come off the lighting/charging coil, and hook up to the voltage regulator. The other two are associated with the ignition coil, and the ground. Is the very high voltage reading coming off of the black/white wire? The brown wire should be attached to system ground.

If you're getting zero juice coming off of either of the yellow (or yellow/black) wires, there may be a problem with your lighting/charging coil. That's not a guarantee, but it's possible. My RIM (running the Chap engine) has the same problem right now, but I've not gotten around to digging into it.

Are you hooked up to a voltage regulator now? Below is the wiring diagram for a CDI engine (no ignition points, so it's a bit different, but the concept's about the same for the discussion.....

[pcs800]

Thanks for the info. I just got back from a local snowmobile shop here, they said there should be ac power coming from two of the wires and the other two are ground. But in your explanation it would seem on of those is ground and the other would used for a kill switch by shorting it to a ground?
This motor does have a CDI, and I am hoping that power from one of the wires is enough to power the lights and things I have installed. Tearing the motor out again and pulling the fly wheel to check the coil is almost not an option at this point which is 1 week away from our deadline to have this machine finished. A friend of mine is a master electrician and is following this thread too, he'll look at the diagram you posted and see if we can figure things out. Thanks again for the response.

[Bazooo guy]

The diagram shows
-the 2 yellow wires from the engine are ac volts for charging.
-one brown wire is ground for the cdi unit.
-the other brown goes to the kill switch and the key switch.
If the key is in the off position or the kill switch is pressed the cdi is grounded thru the
brown/white wire and kills the spark.
you can disconnect the engine coupler and should still get spark but no charging and the kill switch wont work.
that will tell you if the kill switch is shorted or the problem is in the key switch or harness.
red and white wires from the magneto go to the cdi to tell it when to fire the coil.

[JohnF]

The power to run the stuff you are talking about comes from the AC current on the two yellow wires. The AC is rectified to DC and regulated to the proper charging voltage for a 12V system. You need the output from the regulator/rectifier to power the lights and stuff.

The other two wire - one will be terminated on a screw or bolt somewhere on the engine and the other will be connected to the ignition coil. A NO (normally open) switch of any sort (usually in a key switch) goes between these wires to kill the engine.

You want to go from your battery to a fuse panel and from there to your load circuits for your lights and stuff and then the output of the regulator goes to the battery.