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CHECKING DIZZY CAP

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paulsherman

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After re-doing my ignition (new coil, points and condenser) I thought I would check the plug wires for continuity. With each plug wire plugged into the cap, I check for continunity from the inside of the cap to the spark plug end of each plug wire. Everything was fine. But when I checked for continunity in the lead from the center terminal in the cap to the end of the wire that plugs into the coil, NOTHING. I even depressed the carbon thingy in the top of the cap (the thing that touches the top of the rotor, still no continuity. I further checked this wire after removing it from the dizzy and had good continuity.

WHAT THE heck IS GOING ON?

Thank you
 
What's the source of the new cap? Get a good one from Advance Electric, and you don't have to check first to see if they're good. While you're at it, get one two of his "red" rotors; One for now and one to carry. NFI
 
New cap is my plan for this morning. I will head down to Autosports in Seattle. But being the curios type, why no continuity through the center hot lead to the wire that goes to the coil? This is with the cap and wires on my bench.
 
is it possible that there was resistance in the wire preventing the continuity?
 
No continuity from inside of cap to outside. Peter C checked 20 caps on his shelf and all were OK with continuity. All wires are OK
Thank you
 
Corrosion?
Are you just doing a continuity or actual resistance check?
Going through a carbon brush, with spring attached that seats into a socket, with the possibility of corrosion inside the socket (on either side) can easily make a "beeper" continuity checker or light not function.

If Peter C. checked resistance on 20 and it's fine, what is your actual resistance?

I've had to use a small wire brush on the end of a Dremel before to clean up the sockets.

You're in Tacoma, I'm in Kirkland, we have the same gloomy wetness for weather, so the issues I've run into you probably will, too.

Dave
 
I am resurrecting a Bugeye I bought from a guy out in Maple Valley about 5 years ago. It was used for the neighborhood cat box for years and after I solved that problem (smell etc.) I told myself that I would get it started this Spring and I will. I am close. I am heading to Autosports in Seattle soon and will get a new cap and rotor. As always, I will save all of the old ignition components and curse them in the future because they do not function properly.
 
NEW CAP and new rotor. Tweak a few things and it fire up and ran after off and on screwing around with it over the last 5 years. Now will get everything adjusted and in tune. Thank you to everyone.
 
That "carbon thingy" can have a lot of resistance. I don't know what people who make them are thinking--I've seen some with 10,000 ohms, some with only a few ohms. How are you testing for continuity? If you use an ohmmeter, and see several thousand ohms, and you don't have resistor wire or resistor plugs, it probably is OK. Of course, if you do have resistor wire or plugs, that might be too much.

'Course, it's also possible that the thing really is open-circuited. It's a little hard for me to see how that could be, but I suppose it's possible.
 
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