What is the most common cause of overheating?
A. Over time, silicates in antifreeze and hardness in water become insoluble, and combine to form antifreeze gels. This process is accelerated by using aged antifreeze, or tap water with a high concentration of hardness. As antifreeze gels circulate through the system, they reduce coolant flow through radiator tubes, which in turn reduces heat transfer and increases operating temperatures. If antifreeze is not drained, flushed, and refilled every 18-24 months, gels adhere to high heat-transfer areas, baking onto metal surfaces to form scales and deposits. Scales only 1/16 thick decrease heat transfer by 40%, thus causing overheating.
