Hobbies And Interests
Things You'll Need
Instructions
Place the truck on a starter box so that there is no danger of it taking off as you work with the engine during the break-in process.
Tune your fuel intake so that it's running rich. To create a rich fuel/air mixture, remove some of the air from the mix, running it fuel heavy. You'll need to dial in the desired mix by adjusting the high speed/engine temperature and low speed/idle needles on the carburetor, turning the needles clockwise to make the mixture run rich. The rich setting should produce blue smoke exhaust when the engine is running.
Remove the header from the engine and determine the bottom dead center position of the piston by looking through the exhaust and spinning the engine until the piston is in place. Mark the position of the flywheel with the piston in the desired place and then return the header to the engine. By checking the mark you can tell if the piston is in the bottom dead center position, or place it into position by moving the flywheel.
Wrap the engine header in aluminum foil to help the engine get to the temperature necessary for burn-in.
Turn on the engine and let it run at idle until it reaches 190 degrees Fahrenheit in temperature. You can check the temperature with a temperature gauge, which is available at most RC hobby shops. You must get the engine up to 190 degrees Fahrenheit in order to expand the metals in the piston and sleeve in the engine, causing them to adjust to one another and ensuring that they work properly when the truck is running at speed. Run the engine for three minutes at this temperature before turning it off, and allow the engine to cool down. While cooling, check that the piston is positioned bottom dead center in the sleeve; if it isn't make adjustments to place it there.
Repeat the warm-up procedure four more times, allowing the engine to cool completely during the pause between each run.
Fill the fuel tank completely and idle the engine through three full tanks of fuel, allowing it to cool completely during the periods between tanks, again making sure that the piston is positioned bottom dead center in the sleeve.
Run the truck through two more tanks of fuel, only this time with the throttle at ¼ setting. Cool the engine between runs.
Run the truck through a final tank, making tuning adjustments to get the engine running smoothly on the proper fuel/air mixture. Remove the aluminum foil and your engine will have completed the break-in cycle.