DSII and coil problem/question

[Anonymous]

I have a '67 Futura. I've resently put the DSII in with the stock modulator and it had been running fine for about a half a tank of gas. The other day I stomped on it to merge and a little ways down the road it starts missing. Long story short, later that night I was looking under the hood and I could see an arch between the battery (+) side of the coil terminal to the center area.... near where the coil to distributor wire plugs in.
I had a new coil from another 200 and put it in and this time it looked like it was arching from the (-) or tach side. Here is what's running through my head about causes and solutions:

1) Do I need a different coil for the solid state ignition?

2) The red wire from the modulator is attached to the battery (+) of the coil. I noticed on the wiring diagram from the tech article that it should be wired before the ballast wire. Should I rewire it?

3) Did the stock ignition come with a ballast resistor?

4) If I've wired it incorrectly, have I ruined the modulator?

An interesting side note. After I first installed the new ignition, I couldn't get my car to crank. I tried using one of the portable batteries, it turned over a little better, but still no luck. After tearing it all apart and putting it all back together, I put in a fresher and bigger battery and Varoom, it starts up. I guess the newer ignition needed a little more juice to make it work.

Thanks for any ideas. Still no deiseling! Must've needed the higher octane fuel.
-MikeD

 

[Anonymous]

Actually, it sounds like the spark wire that plugs into the coil has a plasma 'leak' in the cap. Do you have a different coil wire to try? (That's the one from the coil to the center of the distributor.)

Another thing that can cause this is a damaged rotor inside the distributor, or a very dirty distributor cap, inside or outside. You didn't say if you used the large cap or the small cap: if you're using the small cap type, then this kind of arcing can happen because the new voltage is much higher than the cap can separate. If using the small cap in particular, be sure to use a very good quality unit, like Accel or Blue Streak. Also, get some of that silicone for the cables and wipe some around the towers where the sparkplug cables attach to the cap - sort of like 'waterproofing' them. This also raises the arcing resistance.

Also check the rotor type: is using a small cap, don't use the rotor with the wide tip - use the narrow tip kind. This will limit the advance you can set to about 8 degrees or less, though. If you use the large cap, use the rotor with a wide tip. This will also allow static timing up to 12 degrees advance, which is a lot.

 

[Anonymous]

Thanks for the suggestions. I am using the large cap and everything is new. I took the car out for a test run with the new coil in it and it seems to be running much better, no missing. I will take some time this weekend and look at the cap and rotor. I read here, at some point, about a guy who was having troubles with caps. And I'll smear the contact goop on it. I might also change the connectors I used. It wasn't a poor job, but it could've always been better. Like, solder all the connections instead of just using the crimp connectors.

-MikeD

 

[Lazy JW]

I take my distributor cap and rotor off and run it through the dishwasher at least once a year. Cleans them up real nice Don't try running the points through though.......
Joe

 

[66Sprint6]

lol, dishwashers are good things, especially for my wire wheel overs, lol :roll: I put them in there right before a big show and then take them out and clean them once again with a chrome polish to keep them that way. Works really well actually. Ill have to try the Dizzy cap sometime!!!
Matt