An interesting issue with my spark plug wires...

[LeviGideon]

So I got my 510 wagon running pretty nice. Adjusted the valves, changed the plugs, put a clean carb on it (thanks to Draker). but it has a bit of a miss that I suspect is a spark issue.

 

When the plug wires are plugged all the way in, the spark is weak, but it fires most of the time, but if I hold the wire back a little and let it arc to the cap, the spark is strong and the car idles a lot more smoothly. I've tested each one individually, and the 3rd cylinder wire is totally normal.

 

I'm sure I need new wires, but could this be another issue of some sort? Points ignition is a whole new monster for me to figure out.

 

It's on an l16, single points dizzy.

 

Also, rotor and cap are brand new from napa.

[datzenmike]

The voltage isn't 20,000 instantly, it actually ramps up to a point where the insulating air between the plug electrodes breaks down and the arc begins. It ramps up very fast though mind you. A dirty plug or bad wires can 'bleed off' some of this voltage as it's rising. When you hold the wire away from the cap you are removing this 'leak' and the voltage has to rise to a higher level before arcing. Like horses lined up before a race all fighting to be first off the line. Some old plugs had a small gap inside them to do the same thing.

 

Are you running NGK BPR6ES plugs?

[Eagle_Adam]

like mike said, get the right plugs, and new wires if you havnt. NGK all the way!!! 

[LeviGideon]

I'm running fresh NGK's. I believe they are BPR6ES but I'll double check it later. So it most likely is plug wires. Good to know. Thanks guys. The car did sit for a good 10 or so years, so just about everything that can go bad is going bad.

[Eagle_Adam]

get NGK wires too