User manual YS DZ140

[. . . ] 2 Use a good quality fuel containing 15% to 30% nitro, and oil content of 20% to 24%. If you use caster oil, no more than 2% is recommended. DO NOT USE FOUR CYCLE FUEL DUE TO LOW OIL CONTENT. TAPPET ADJUSTMENT Tappet clearance is preset at the factory. Adjustment, if you needed, should be checked after the initial break-in. For maximum performance, valves should be checked as normal maintenance. [. . . ] With the restrictor in, the RPM drop will be 300 to 400 rpm. COOLING In some aircraft installations, cooling of the engine and fuel pump is extremely critical for optimum performance. Ducting which forces incoming air around the cylinder head is recommended. Be sure to provide adequate size inlets and outlets for air traveling through the cowling. IMPORTANT Silicone rubber is used in the YS engines. Only use glow fuel or methanol for cleaning. Gasoline and other volatile solvents will damage the silicone if used. Do not use petroleum based oils as after-run lubricants. 111. 5 Fuel Tank Clunk 134 fig. 1 3 After the engine has started, slowly bring the throttle up to full. Set high speed needle so it is running at a good rich setting without the glow driver. 4 After the initial 20 minute break-in, mount the engine in the aircraft and set the high speed to a richer than normal setting for the first 10 flights. This will help to lubricate all moving parts. FEATURES The DZ140 was developed for serious aerobatics competition. The new design has been in the development stage for more than 3 years. It differs from previous YS Engines in that it does not use a high pressure fuel system but rather a true fuel pump. *Crankcase supercharging system unique to YS 4 stroke engines *Fuel injected *Convenient fuel pump adjustment *High horsepower output with long service life GLOW PLUG Select the most appropriate glow plug from those designed specifically for 4 cycle engines. Glow plug selection greatly affects the maximum engine output and low idle. If RPM's decrease or stop when the booster cord is removed, replace the plug. We recommend the YS#4 or OS Type Fplug for maximum performance. INSTALLATION WE RECOMMEND THAT THIS ENGINE BE MOUNTED ON A SHOCK ABSORBING SOFT MOUNT PROPELLER INSTALLATION Due to the high output power of the 140DZ engine, it is supplied with a double locknut system for added safety. If you use any other type of spinner or prop nut device, make sure it is of the double nut type. 1 Mount the propeller and tighten the rear nut. Next, tighten the front nut as shown in fig. 2. The rear nut has an offset shoulder so the front nut will secure itself to the rear nut. [. . . ] With this filter, you must remove the cloth portion of the filter and leave both the metal filter screens in place. Front Nut Rear Nut fig. 2 The low speed adjustment is the regulator screw on the front of the engine. Turning the screw clockwise will richen the idle mixture, and counter-clockwise will lean the idle mixture. It is preset at the factory but may require further adjustment depending on fuel and conditions in your areas. 1 Wait until the engine is up to operating temperature before adjusting the idle mixture 2 Close the throttle gradually to an idle ( approximately 2, 200 rpm ). [. . . ]