View single post by Tom Bradley
 Posted: 11-15-2018 03:13 am
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Tom Bradley

 

Joined: 07-15-2013
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 If one of the carbs is malfunctioning I would expect that the corresponding pair of spark plugs would show some evidence of too rich or too lean mixture while the other pair would not.

Intermittent problems like this are often caused by bad electrical connections. Doing the described performance check (revving up to high RPMs?) can make loose connections worse. Check that there are no loose connections in the ignition primary circuit as well as loose HV cables and loose distributor cap. If you have a pertronix ignition and high-power coil then bad spark plug cables or plugs can cause the spark to jump to other places, causing damage to the distributor cap. Do you know what this damage looks like? It is often tiny and hard to find. Replacing the distributor cap may be a good idea.

I have read that the pertronix ignition is sensitive to electrical interference. Make sure you have resistive plugs or cables.

Do you know if your voltage reading was OK when this happened? I once had a Lucas alternator that cut in and out after the engine warmed up that caused ignition problems.

Intermittent problems are very frustrating.

Tom