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Discussion Starter #1
checking the ignition coil on 1976 CB500T, following the procedure in the Clymer manual.
shorting the 2 black/white leads and checking continuity to plug wires to compare for siimilar readings side to side.
with the plug connectors off the wires I get 10.3 and 10.4 ohms.
Q. does it matter what readings as long as they are the same?

with the connectors on the wires I get 19.0 ohms on one side, infinity on the other.

if I check continutiy of the caps alone I get 10.1 on one and 8.3 on the other.
the one that reads 8.3 when tested alone is the one that reads infinity when attached to the wire.
the reading follows the cap.
does this make any sense to anyone? do I just need new plug caps?
 

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Please clarify - you're measuring from the spark wire to the low voltage wires, with the spark plug caps off, and getting 10 ohms, right? That's good. Then, you install the spark plug caps, and take the same measurement, from the spark plug cap to the low voltage wires? And one measures 19 ohms, the other open? If all this is true, the one that reads open is not actually connecting to the wire, or its internal connections are open when connected to the wire. Apparently, you don't have caps with resistors in them, because they would read about 5000 ohms. Also, pressing the meter leads into the caps could push the internal connections together in the 'bad' cap, making it read good, even if it is cracked open inside.
 

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Discussion Starter #3
Please clarify - you're measuring from the spark wire to the low voltage wires, with the spark plug caps off, and getting 10 ohms, right? That's good. Then, you install the spark plug caps, and take the same measurement, from the spark plug cap to the low voltage wires? And one measures 19 ohms, the other open? If all this is true, the one that reads open is not actually connecting to the wire, or its internal connections are open when connected to the wire. Apparently, you don't have caps with resistors in them, because they would read about 5000 ohms. Also, pressing the meter leads into the caps could push the internal connections together in the 'bad' cap, making it read good, even if it is cracked open inside.
You have it right, and when I switch the caps the bad reading follows the cap which indicates to me the problem is internal to the cap, and not a bad connection to the wire.
You say "good" to the 10 ohm reading, so I assume that is an OK reading, yes?
So my take on this is that I have a bad cap...sound right?
 

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Yes, 10 ohms sounds about right for the coils. I would recommend resistor caps (they show up on ebay from time to time), as they cut down on radio noise.
 

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Sounds like the caps to me. Bad internal connection. When u put them together and it reads inf or open then there is no connection or most ohms than ur meter is set for.
 
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