User manual YS FZ140-SPORT

[. . . ] This concludes the break-in procedure, It is advisable to always use a slightly rich setting to keep the moving parts lubricated, even atter the break-in period . TAPPET CLEARANCE ADJUSTMENT 1. No adjustment is necessary until atter 1 hour of operation (including break-in period). Clearance adjustment should be done when the engine is cool. When the engine temperature is high, clearance is higher due to thermal expansion. [. . . ] Notice the impression made on the crankshaft counterweight. Position it directly straight down or in line with the case outer seam line. When reinstalling the cam gear, the side with a point mark should be facing the opening of the gear box, Note that it should also be mounted with the point mark located towards the top of the engine just below the cam followers. FEATURES PROPELLER INSTALLATION The new FZ140 Sport uses the best features of our very successful 120 and 140 engines, combined in an easy-to-operate and economical package. It is ideally suited to aircraft which previously used the YS120, as the mounting dimensions are the same. An added bonus is that the weights are essentially equal, and the FZ140 Sport will turn larger propellers for higher flight performance. Due to the high torque of the FZ140 Sport , we have equipped It with double locknuts for safety. Mount the propeller and tighten the rear nut. Next, tighten the front nut as shown in Fig. 1. Select a good quality propeller that will turn in the 8, 000 to 9, 000 range, We recommend sizes 14x14 through 16x11 LOW SPEED ADJUSTMENT This engine is equipped with a new low speed needle valve to adjust the mixture from low to mid throttle. This needle valve is located on the side of the throttle barrel opposite the throttle arm (Fig. 1) 1. Open the low speed needle valve to 1 1/2 turns from fully closed position. The low speed needle valve should be set after the high speed needle valve has been adjusted. Close the throttle gradually to an idle (approximately 2500rpm). Let it idle for 20 to 30 seconds and then slowly advance the throttle. The adjustment is satisfatory at low speed if transition is smooth at this time. If the engine is runnlng rough on idle, the low speed mixture is rich. If the engine starts to speed up and dies on idle or starts to detonate, when advancing the throttle, the mixture is lean. Turn the low speed needle valve clockwise to richen and counterclocwise for a leaner mixture (note that the direction of the low speed needle valve is opposite the high speed needle valve). Adjustments to the low speed needle valve should be 1/8 to 1/4 of a turn increment at a time to achieve smooth throttle response. DIAPHRAGM AND CHECK VALVE DISASSEMBLY Diaphragm: 1. Remove the adjustment screw of the valve, and then remove the inside valve and spring. Clean the inside with alcohol or appropriate cleaner. Reassemble. Screw in the regulator screw until flush with the diaphragm body. [. . . ] Match the direction of the check valve arrow to fig. 1, with the arrow facing towards the tank. It is highly recommended that this engine be mounted on a vibration absorbing soft mount. MUFFLER INSTALATION We recommend mounting the muffler outside the cowling so that proper cooling can be achieved. If the muffler is mounted inside the cowling, extra cooling air is necessary to prevent muffler failure due to excessive heat build up. Silicone rubber is used in many parts of the YSengine. [. . . ]