Re: IML: Ignition failure II

Kenyon,

I would like to offer my $.02 for what it's worth. The symptoms you described may be indicative of a vacuum leak. This would cause a lean misfire in one or more of the cylinders under wide open throttle (feels like no spark to a couple of cylinders), this misfire would be masked when cold by the artificial enrichment provided by the automatic choke and the vehicle would still appear to run well in the mid range. Other factors you mentioned (Mallory ignition, replaced carb, etc.) tend to be the type of repair attempts made when a vacuum leak is present. I would suggest you let the car warm up to operating temp (when the rough idle is apparent) and then using a spray bottle of water, liberally spray water around the base of the carb, all the vacuum hose fittings, and where the intake meets the heads to see if the idle quality improves, if it does, you have located the source of the vacuum leak. This may also provide you with a method for finding leaking spark plug wires as water conducts electricity and when sprayed on a bad plug wire will cause arcing. CAUTION: do not use carb cleaner or WD-40 or similar chemicals in place of the water as they are flammable and can lead to false indications when sucked into the air intake stream while diagnosing the problem. I look forward to hearing what you find.

Randy

73 Newport (wants to be an Imperial)

----- Original Message -----

From: Kenyon Wills

To: mailing-list@xxxxxxxxxxxxxxxx

Sent: Thursday, March 24, 2005 3:49 PM

Subject: RE: IML: Ignition failure II

Chris Hawkins <imperial1966@xxxxxxxxx> wrote:

Kenyon,

If your car had an electronic ignition, it likely had
a different ballast resistor and coil. I would make
sure both are correct of a 1960 distributor. If the
wrong ballast resistor has been used with your
point-style distributor, they may be burned.

=========

Both were replaced with correct parts (this is a 72, by the way).

At this time I am starting to focus on the Holley carb. The car had one and it tended to stick at WOT. I found this undesireable and found an identical carb that had been sitting for 15 years in a dry shelf.

I sense that the carb is perhaps so lean or that at idle the idle circuit is not operating peoperly, as the car runs great in the middle range. I dunno, but as I pay more attention to what the symptoms are, I'm guessing that the car wants a different carb. It did not exhibit these symptoms before the carb swap (same electricals)- just scared the snot out of me when I romped on it and it didn't back down. The car sat for awhile, and I'm now certain that there are fresh surfaces on the pads and rotors - the car used up one of its nine lives as I stood on the brakes and slapped the ignition off.

I'll write more after I get a different carb.

Kenyon Wills