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Starting the Stopped
by Lonnie Fallin 

Our Classics with their big displacement engines sometimes are very difficult to start when they have been run for a while or when they get hot.

There can be several reasons for this and hopefully some of the following suggestions will help you solve the problem. Most of them are just common sense but when you are by the side of the road and your car won’t start, common sense will not always prevail. So the best solution is to hopefully prevent the problem before it happens.

Needless to say, there can be many causes for an engine not to start. So let’s assume that your starter is working as it should. You have the points set properly. The plugs aren’t fouled or gapped improperly. Your coil is okay and the generator and regulator are working as they should. The fuel pump works and the carburetor is not plugged.

Our Classics have six volt systems and you always hear about converting to an eight- or twelve volt system to solve the problem, but is that really necessary? When cars were used as regular transportation the six volt system was fine when set up and maintained properly.

Therein lies the problem. Most of our Classics spend long periods of time in storage and the batteries may discharge. The battery can start a cold car but not a hot one. You can only tell if your battery is fully charged by using a voltmeter. A full charge will be 6.3 volts. The maximum voltage from a six volt battery will be between 7.2 and 7.4 volts. You need at least 5.1 volts to crank your car and no less. A one volt drop in cranking voltage results in a 1,000 volt drop at the ignition. Another problem is the size of the battery cables. The old six volt cables are thick and have a heavy copper core. If you have purchased a new cable from the parts store the odds are it is not the correct gauge and could even be an aluminum not copper core even though it may look thick because of the insulation. You should have a cable made up that meets the specifications for your car.

 Now you have everything just as it should be and it still won’t start when it gets hot. The one single thing that will negate everything else is the simplest of all and usually the most overlooked: THE GROUND. When most cars are restored the frame is painted and the ground from the battery to the frame makes a poor contact unless the ground is to bare metal. Also you need a good ground from the engine to the frame so that you have a good electrical circuit without the paint interference.

So have a fully charged battery, the correct sized battery cable, and proper grounds and if the other parts are functioning properly you should start up, hot or cold.

Courtesy of The Classicist of the Colorado Region

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