440 whip spark issue

[tkjoe]

Ok I'm really lost here, I just rebuilt a 78 440 cuyuna. I have spark on PTO side but not mag side. I hooked up a continuity tester to the blue/red wire coming from stator. I have power on that wire up to the external coil. nothing past. New external coils, plug wires, plugs. ground wires seem good. tried hooking extra ground to the frame and no difference. any suggestions??  am I overlooking something?

[80whip440]

Try and swap the coils from side to side.
If the problem follows the coil, you can test them as shown in this thread: Testing Bosch coils 
If the coils pass, you need to dig deeper. Make sure the wires and caps are seated  (screwed on) tightly.

[tkjoe]

I swapped coils, I have juice right at the wire until i plug it into the coil. I also unplugged the wire harness, then no spark either side? but always have spark at the flat blade wire connector. added a ground wire also. unplugged kill switch. now after doing all of this no spark at the plugs either side. Brand new coils out of box and plug wires. I'll have to test coils and check plug wires.

[tkjoe]

Ok tested coils, they ohm out, now if I unplug the wire to the coil that does spark, the other one will spark? almost like not enough juice to fire both at same time? if I hook up the continuity light they both light up when I pull it over. just don't know if its enough juice. I think I may need to switch out the stator?

[weverat]

Sounds like one set of points is working, and the other is not. I like to take the points right out and clamp them in the vice, then clean them with 600 or 1000 grit sand paper.

Finish clean up with brake clean and a clean white business card. Just spray the corner of the card with the brake cleaner and drag it through the points.

Keep digging, you will get it to spark good. Those JLO,s are dam nice motors.

[obj1]

right on weve! dirty points and outta time.

[tkjoe]

I was wondering about points, just though with juice to both wires when I pill it over, that the points were firing? That will be my next step. thanks guys

[tkjoe]

Ok, I changed points and reset timing, but before I put everything back together I'd like to check the internal coils and lighting coils. Does anyone have the specs/ procedure for those?

[weverat]

Checking resistance / measuring continuity on those coils does not seam to help me.

If the primary ignition coil is working it will have spark. I do not know how to test it, except try a known good one.

The lighting coils you can test with the engine running. You check voltage at idle, and also with engine revved up a little.

The voltage rises as the engine revs

Then you can check voltage after the regulator, it should hold at about 12-13 volts. Another way to prove if the regulator is working is to disconnect the head light, start and rev engine, if it blows the tail light, regulator is not working.

The late model Cuyunas have 1 ignition primary coil and 2 lighting coils - 1 is 60 watts, and the other 15 watts, 75 total.

Don't tell OBJ, I sometimes remove the big 60 watt coil (yellow wires), and use only the little 15 watt (green wires) to drive the tach, and no regulator.

[tkjoe]

thanks Weverat

[tkjoe]

Got it back together, good spark on both, thanks Guys

[75whip]

Tkjoe what was the result of your problems with this? I was following the post.

[80whip440]

Inquiring minds want to know.........

[80sting440]

I'm going with weverat and obj1...one set of points needed cleaning?......waiting....

Rene

[tkjoe]

It was the points, tried cleaning them and nothing, installed a new set and bingo had spark!