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Bogging Down

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Giovanni59

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Hi,
I had a Petronic Electronic ignition put in my 1958 100-6 and after about an hour of driving the car bogs down. I replaced the plugs and there was a vast improvement but after a while it went downhill hill again. Am I running too rich? Do I need a "hotter" plug to help self clean?
Different plugs? The car came with Bosch, the mechanic put in Champions, I replaced them with NKG. Thanks for your advice.
John
 
HI John, I can only guess that the plugs are too cold. A good plug to run is the Bosh WR7DP. You did not state whether you are running the original coil or an upgrade.If using an upgraded coil I suggest the plug gap be opened up to about 0.030"-or-0.035" and the carb mixture be checked for too rich running.---Fwiw---Keoke
 
One of the symptoms of a coil going bad is after it heats up, it's performance degrades. If you still have your original Lucas coil, it is probably the problem. Put an ohm meter across the primary terminals of the coil. A good coil will be close to 3 ohms. If your coil reads 6 ohms, the output power is 50% of what it was new. The Petronics coil is a good match to the petronics ignition unit. Also, Keoke is correct about the .035 gap on Bosch platinum plugs with a 40kv coil plus the Petronics unit.
 
I forgot you have a 58 100-6 . The 3 ohm value is correct for my 65 bj8, But I don't know if the 100-6 used the same coil or not. Perhaps someone that has one and knows can post an update.
 
Hi Ed,
You are correct. All Healeys used a coil without external ballast. An acceptable range would be about 2.6 to 3.2 ohms primary winding resistance.
D
 
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