Triumph TR7 TR8 Clock Repair

The 1975-1982 Triumph TR7 and TR8 car clocks contain 2 defects that can effect its successful operation in the vehicle's local environment. This document describes how a person with a limited skill level in electronic component soldering and automotive vehicle repair can correct these 2 particular defects to obtain a more reliable Triumph TR7 TR8 vehicle clock. The first defect, or shortcoming, is that the clock was designed for approximately a +25C +/–10C temperature operation environment. This was a common automotive design standard used into the mid 1990's by a few major auto companies. Thus in colder climates, such as at 0C, the clock will just stop. The second defect, is that the clock's timing mechanism is critically balanced between the force of a timing spring, the electro-mechanical force applied via an electric coil, the distance a feedback magnet is from a feedback coil, the vehicle's voltage, the amplification provided by a transistor, the friction of the clock's escapement gears and many other tolerance items. There is a spot where everything balances, the clock "stalls" and stops operating. The clock will only start operating again, if the "right" kind of bump in the road (vibration) or electrical transient (like starting the car) is encountered to jiggle the clock's pendulum back into motion.

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