3 All car engines must use a properly oiled air filter High-Speed Needle: 2 /4 turns out (counterclockwise) We recommend using an spin starter or starter box for to keep dirt out of the engine. Any dirt that enters from closed. the initial starts, even with a pull-start equipped engine. the carburetor can immediately destroy your engine. 3 You may need to “blip” the throttle on the transmitter Low-Speed Needle: 2 /4 turns out (counterclockwise) We recommend LOSB5020 as an excellent choice from closed. (applying throttle on/off) while trying to start the engine, for a quality air cleaner. Service the air filter after as new engines are more difficult to start due to the When checking the adjustment of the low- every hour of running, by washing out the foam filter tight piston/cylinder fit. speed needle, it is crucial that the throttle with warm water. Dry the filter then re-apply air filter slide is closed completely when turning the Never start an engine above 1⁄4 throttle. oil to the foam filter. needle and that you do not over-tighten the Immediate damage to your engine can and will occur. Carburetor Adjustments needle. Use an engine tuning screwdriver (LOSA99176) to make this job easier. When When the engine starts, the exhaust should emit lots Your Losi engine comes equipped with a precision you feel resistance in the needle, immediately of blue/white smoke, indicating that the engine is Owner’s Manual slide-valve carburetor. Take a moment to review the stop turning and begin turning the needles excessively rich (a good thing during break in). During pictures below to familiarize yourself with the various counterclockwise, counting the number of the first tank of fuel, you may wish to set a higher than Congratulations on the purchase your new Losi functions of the carb. Loosening the nut located on the turns from “closed.” normal idle speed and/or leave the glow plug igniter product. Before installing your engine, please side of the crankcase under the carburetor body will attached in order to keep the engine from stalling. read these instructions to ensure reliable and allow you to rotate the carburetor to properly fit your Starting Your Engine Drive your vehicle around while “blipping” the throttle trouble-free performance. particular application. Make certain to mount the throttle for the First Time and avoid operating the engine at full throttle for arm to the side required by your particular vehicle. more than 2–3 seconds at a time. Consume the entire Using the Proper Fuel and Glow Plug Although preset at the factory, some changes in the The first start of your engine is the most critical time of first two tanks of fuel in this manner. After the first two Using the proper fuel and glow plug is critical in order needle setting can occur during shipping and handling. the engine’s life, dictating how well it will perform. After tanks of fuel, begin leaning out the high-speed needle to achieve maximum performance and reliability. installing the engine in your model and inserting the High-Speed valve 1/8 turn at a time. It generally takes about 5 You must use fuel, glow plugs and air filters that Needle Valve glow plug, turn on your radio system and attach a glow or 6 tanks of fuel before you’d want to start tuning are specifically designed for model car/truck/buggy igniter to the glow plug. Place your finger over over the exhaust and turn the engine over with the starter for for “maximum” power. applications. Never use any type of model airplane Low-Speed glow fuel! Use of model airplane fuel can damage Needle Valve 2–3 seconds to prime the fuel line.(This should only your engine and immediately void any warranty. be necessary when the engine is cold, do not touch the exhaust pipe when the engine is warm.) We recommend using Losi Nitrotane™ fuel, providing Should the engine become difficult for the spin start to the best combination of power and fuel economy. Losi Fuel Inlet turn over, the engine may be flooded (hydro-locked). fuels are vigorously tested, researched and formulated (Adjustable) Excess fuel between the cylinder head and piston will to deliver excellent power as well as engine protection. Leaner not allow the piston to travel through its full range A glow plug has been included and is ideal for of compression, effectively “locking up” the engine. breaking in your new engine. In fact, during the Faster Idle Slower Idle (clockwise) (counterclockwise) Should this occur, immediately remove the glow igniter break-in procedure, it is not uncommon to go through Idle Stop from the plug. Using a glow plug wrench (LOSB4603), Adjustment one or two glow plugs, as microscopic bits of metal remove the glow plug and turn the model upside down (from the cylinder/piston wearing in) bond themselves Leaner and rotate the flywheel to clear out the fuel, re-install the to the plug element causing glow plug failure. We glow plug and start again. recommend the Dynamite DYN2495 Glow Plug as this You may need to “blip” the throttle on the transmitter is the best glow plug for this engine. The DYN2495 (applying throttle on/off) while trying to start the engine, Plug has been designed to deliver an ideal balance of Fuel Inlet Low-Speed (Adjustable) Needle Valve as new engines are more difficult to start due to the performance and longevity. tight piston/cylinder fit. We suggest the following settings for breaking in your engine using Nitrotane 20% Sport Fuel. Do not skip this process of breaking in a new Tuning the High-Speed Needle After Operating Your Engine Troubleshooting Guide engine! Should you choose not to follow these To obtain the correct high-speed needle setting, start Periodic maintenance must be performed in order to Problem Possible Cause/Solution procedures, you risk damaging your engine the engine and drive your vehicle around for a minute keep your engine in proper operating condition. After Engine won’t start • Clogged fuel line during the first tank of fuel. or two, applying full throttle frequently. Place a drop each day of running, it’s critical to use high quality • Bad or improper glow Your patience during these procedures will be rewarded of water on the cylinder head. If the water sizzles away after-run oil to protect the internals of the engine and plug by an engine that performs reliably and to its maximum (evaporates immediately), the needle setting is too help prevent corrosion. The methanol used in the fuel • Glow igniter not power potential. First run attempts can be more lean. A correct needle setting will result in the water attracts moisture that can cause corrosion (particularly charged frustrating than with other (less powerful) sport engines, evaporating after 3–5 seconds. If the water does not in the ball bearings). Follow these steps after running so take your time—it will be worth the wait. Glow evaporate, chances are good that the needle setting is your engine: • Bad or old fuel plug failure is a common occurrence when breaking too rich. Lean the needle 1/16 of a turn and run the 1) Empty all fuel from the tank and fuel lines. • Glow plug is bad in a new engine. If the engine dies when throttle is engine again, adjusting the needle setting to get the 2) Remove the glow plug and air filter and add applied the plug may be bad. Remove the plug and desired evaporation time. 5 to 6 drops of a quality after-run oil into the Engine starts, then dies attach the igniter and check for a bright glow. If all the • Engine flooded Check the temperature each time you change carburetor and cylinder head openings. Turn coils are not glowing it should be replaced. If the new • Pressure line blocked or the needle mixture. Do not let the engine the engine over a few times to distribute the oil plug exhibits the same behavior the needle setting is disconnected overheat, as this will damage the engine. throughout the engine. probably too rich and should be adjusted. • Bad glow plug Tuning the Low-Speed Needle 3) Clean and inspect the engine, air cleaner and Setting the Needle Valves fuel system. The low-speed needle (also referred to as the idle Engine starts and runs • High-speed needle too When tuning the needle valves for maximum mixture or idle needle) should be set after you’re for 1⁄2 tank, then quits lean performance, adjust them in small increments, satisfied with the high-speed needle setting. After • Hole or tear in fuel line 1⁄16 turn at a time. achieving the proper operating temperature, reduce the • Bad glow plug or idle An engine should not be run too lean; doing so engine throttle to idle and pinch the fuel line with your speed set too low severely shortens the life of the engine. When an fingers close to the carb fuel inlet nipple. If the engine engine is set too lean, it will run very strong at dies immediately, the low-speed needle is set too lean. • Overheated engine first but will soon begin to sag and hesitate or stall If the rpm’s increase dramatically, the setting is too rich. (too lean) when accelerating. The ideal setting results in the rpm’s increasing just a • Improper needle The best way to tune an engine is by using an infrared slight amount after pinching the fuel line. settings temperature gauge (LOSA99171), but you can also use water to check the head temperature (refer to “Tuning Idle Stop Adjustment the High-Speed Needle”).