1971 ts250 electrical problems

[jh128]

I have a 1971 ts250 I recently replaced my igniter coil it ran good for a week and now it runs good for 30 minutes or so then it dies and fires back up once it cools down abit I haven't tested the coil I just put in it yet but I was wondering if anyone else had any issues like this

[rngdng]

I have had similar issues in the past. In my case (RZ350) it was the CDI box. A coil can act like that, too.



Lane

[jh128]

Is there anyway to test a CDI box?

[rngdng]

I can only do it by swapping it for a known good one.


Lane

[jh128]

Thanks man I'll see if I can find one

[MikeD]

Is there anyway to test a CDI box?

not directly, but you might be able to go by process of elimination. usually the crank trigger circuits have a resistance across the signal pickups that you can check continuity for, and if you have access to a scope you can watch them go high and low as you turn the crank so that the trigger passes over the signal coils. if you've got that at the plug side where it enters the CDI then you've got signal entering all the way to the CDI. you can check for 12v at the coil/s with power switch in the on position (usually the orange wires of some sort), and continuity between the other side of the coil/s and the CDI which (black/orange, etc). CDI provides the ground when the trigger passes by the signal generators. Check the resistance of the coil wirings (key off) and the plug wire for the correct resistance range, and the caps for resistance as well. if its got power to the coils/s, and trigger signal from the trigger circuit, power to the CDI plug, ground to the CDI plug, and good connections from the non-power side of the coils to the CDI plug, and you still have no spark then something may be up with the CDI since there isn't much left. It's not a guarantee though

not sure - can one check for ground on the wire coming back from the coil when the trigger is sent by the signal pickups with a meter on a CDI without blowing the CDI? I know with points you can ground the points to complete the coil ground circuit which causes the voltage in the coil secondary windings to trigger the coil and fire the spark plug without having to spin the crank. Is there an equiv CDI test?

The factory used to make CDI test boxes, see them now and again on eBay. Haven't watched, but might be helpful based on the description: https://www.youtube.com/watch?v=lYzrByJUoGY" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;. I searched for "suzuki cdi tester", a few interesting links turned up. Good luck