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3 good tune-up tips for beginners, back to back (#2)
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Posted by RKS on May 31, 1999 at 04:22:58 from (171.211.172.216):
(2) - SETTING THE POINTS AT THE PROPER GAP: OK, so you have the points and condenser installed without missing a screw. Good for you, but are the points set correctly? You say you set the point arms so that the gap was exactly where the mfg recommended and then tightened the screws, so yea, you think it's right. Well, remember that the point gap is absolutely critical to proper operation of the engine. The mfg designed the system with the intent that the points will lose contact as the point arm rises up the "cam lobe." At a precise position, the points will "break" and the coil will fire and the spark will occur. If your points are not correctly set, this will not correspond with the mfg's recommendation and the spark will be mistimed. Even if you subsequently force the timing to the correct mark with the use of a timing light and manual adjustment of the distributor, you won't be setting the "dwell angle" of the points correctly and the charging of the primary winding of the coil will be incorrect, leading to poor spark generation and incomplete combustion. The mistake is to assume that only once is enough to measure the point gap. When you secure the screws that hold the points, you will alter the gap as you tighten the screws. Do it slowly, feeling and measuring as you go, so that the feeler guage "just slightly drags" in the gap at the proper setting, when the last amount of torque is applied to the securing screws. Only then will you know the point gap is correct and that you haven't changed it by tightening the screws. RKS
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