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Mechanical Help Please (fouled plugs/erratic idle/hard start)

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From what you said in your first post the engine has not run properly since being rebuilt. The calibration of the carb may be off for your application. Just as a hail Mary, I'd try removing the mixture screws and squirting some carb cleaner in the screw hole using the supplied small "straw". Reinstall the screws at about 1&1/2 turns out. I seriously doubt it will fix the problem but, it is quick and easy to try.

Calibration kits are available from Edelbrock based on the specific carb you have (I believe there are 4 650 cfm edelbrock carbs, 2 with electric chokes).

Here is a link http://www.edelbrock.com/automotive/mc/carburetors/access-calibration.shtml

Please let us know what you find out. Chuck

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Well, after a long week or so of troubleshooting I have the fix/fixes...The distributor points were not gaped correctly (way too close), and this was causing an erratic spark. I also discovered a spark plug wire that was not working consistently. The erratic spark and the wire were the reasons for the missing/thus the plugs were fouling due to the extra fuel in the chamber when it did spark. I am thinking the points may have moved when I was out driving it that day. I adjusted the points and also swapped the condenser for good measure. This fixed my idle issue. (Still a little unsure why this was only an issue at lower RPMs and why when the engine heated up it smoothed out for a while)


The second issue was that once under a load and driving the engine would surge. I am fairly certain this was due to the timing being too advanced, and the distributor vac advance advancing too quickly. Tomorrow I will start doing some road testing on this issue and see if I can get it set correctly. Right now, when the vac advance is hooked up it is backfiring out of the exhaust on the driver side. I still have some fine tuning to due (probably adjust the idle set screw on the driver side). But, the car is starting and runs very well without the vac advance hooked up, so I am definitely ahead from the last week!



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Glad to hear that you have resolved the issue, before I switched to Ford Duraspark II distributor I had a breaker point distributor and still recall some of the experiences with points and condenser failing.

1971 Mustang

Grabber Lime with black deluxe interior

302 engine with C-4 transmission and 9" rear end with 3.50 gears


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Upon further testing and investigation, points suck. I was still having issues when it was under a load. I broke down and swapped the points and condenser with a PerTronix electronic ignition. It fired up perfectly and ran like a champ. No hesitation or bogging under a load. That will be the last set of points I ever deal with. It was definitely worth the $85 dollars.

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