At the beginning of the 20th century there was no modern term, but motorists were already engaged in tuning and fine-tuning of their cars.
Valve mechanisms were the constant concern of the owners of "motor strollers." Design imperfections (in particular, the lack of an air filter), poor quality of materials, “floating” ignition, and finally, fuel of unknown origin contributed to accelerated wear and sometimes damage to valves. In addition, on most cars of the beginning of the century, for the sake of simplicity and cheapness, the possibility of quick adjustment of valve clearances was not provided. If necessary, the gap was set by filing (!) The rod. It is easy to imagine the accuracy of such an adjustment.
Everyone wants the engine of his car to work with full dedication, and many dream of boosting the engine. Cars of the beginning of the century were a wonderful object for creativity. But before you start improving the factory design, you had to grind the valves. The great-grandfathers did the operation familiar to many in much the same way as the great-grandchildren. However, often, in addition to lapping, a more serious treatment was required: deep scratches were found on the valves. Parts stores are rare, ordering parts at the factory and waiting for their shipment is a long song. You can grind the valves on a lathe. Only a well-equipped workshop is not always at hand. Instead of the machine tool, “arm” motorists came up with a simple device (Fig. 1). A hole was drilled in a cylindrical blank with a diameter slightly larger than the valve, and two symmetrical grooves were made from the sides. Cutters were inserted into them, fixing the latter with screws. Having inserted the valve into the hole, a standard spring was put on it from below, fixing it with a locking washer. Turning the valve with a screwdriver (there was a slot on it) or another improvised tool, brought the surface to the desired cleanliness.
The valves are in order, now you can think about adjusting. As a rule, craftsmen made threaded spacers between a specially shortened valve stem and a pusher. One of the most successful - simple and reliable - designs is shown in Fig. 2. A threaded sleeve was put on the pusher, fixing with a pin. They screwed a hairpin with a tetrahedral upper part - turnkey. A lock nut was placed over the sleeve. By loosening it and rotating the pin, the valve clearances were adjusted quite accurately. As you can see, the design is similar to the modern one familiar to the owners of Lada, Volga, and Muscovites.
The second version of the adjusting device is closer to those who repair "Samara" (Fig. 3). A double-sided metal cup was placed between the valve stem and the pusher. Washers were made from a steel sheet 0.1 mm thick. Putting them in a cup under the valve stem, we achieved the necessary clearance.
Despite the “notions” of cunning motorists, adjustment and sometimes grinding of valves had to be done almost once every few hundred kilometers. But this didn’t bother the great-grandfathers - tuning cars carried them no less than riding.
Fig. 1. Device for processing valves: 1 - washer; 2 - spring; 3 - valve; 4 - cutter; 5 - screw.