User manual YS 140 LIMITED

[. . . ] Adjustment if needed should be checked after the initial break-in. For maximum performance, valves should be checked as normal maintenance. Clearance adjustment should be done when the engine is cool. The proper clearance should be set 0. 04-0. 1mm or 0. 002-0. 004 in. [. . . ] As aircraft increases in size, so does the need for power. With a few modifications internally, YS was able to generate more power in the same 140 case. The YS 4 cycles are so unique, almost every square inch is used in some way to produce power. * Supercharged * Fuel Injected * Regulated and Pressurized Fuel System * High and Low Speed Adjustments PROPELLER INSTALLATION Due to the high torque of the140L engine, we have equipped it with a double locknut system for safety. Mount the propeller and tighten the rear nut. Next, tighten the front nut as shown in fig. 2. The rear nut has a offset shoulder so the front nut will secure itself to the rear nut. Select a good quality propeller that will allow the engine to run at maximum speed between 8, 000 to 9, 000rpm range. We recommend sizes 14x14, (15x12 through 14), (16x11 through 14). 1. Factory starting position is 1 1/2 turns open from the fully closed position. The low speed needle should be set after the high speed needle has been adjusted. Close the throttle gradually to an idle (approximately 2, 000rpm). Let it idle for 15-20 seconds and then slowly advance the throttle. The adjustment is set when low to high speed has a smooth transition. If the engine is running rough at idle or to rich, turn the low speed needle counterclockwise to lean out the low end. If the engine speeds up at idle , the low speed mixture is to lean. Turn the low speed needle clockwise to richen the mixture. If the engine is to lean on the low end, it can detonate and stop when transition from low to high RPM. DIAPHRAGM AND CHECK VALVE DISASSEMBLY Diaphragm; 1. Remove the regulator assembly by removing the two allen head screws. Disassemble the regulator and clean with alcohol or appropriate cleaner. When reinstalling the regulator, use a new gasket and note that the small casting tab on the regulator goes towards the propeller. Open the check valve by rotating the body counterclockwise. [. . . ] Open the high speed needle 2 1/2 turns from the closed position. Open the throttle fully and slowly turn the propeller 10 times. This will prime the engine and pressurized the fuel tank. Close the throttle to the idle position and connect the glow driver. [. . . ]