| [ car ] in KIDS 글 쓴 이(By): Nutrino (떠얼~ 루) 날 짜 (Date): 1995년03월04일(토) 03시23분27초 KST 제 목(Title): idling... idling... warming up! Leaving a car's engine to idle is a killer action to a car fanatic's point of view. It is during idling and prolonged low speed driving that puts up extra stress on the timing belt which turns the crankshaft pulley and syncronizes the ignition of sparkplugs with optimum BTDC of the compression stroke of the piston. Now, if this system messes up, your engine is liable to so many problems... but! its not hard to correct. An average American does not warm up his or her car in the morning... I noticed, but he tends to leave the car idling with heater or air conditioner on while unattended for several minutes... this is very bad habit! Now back to the issue of warming up the car. To the best of my knowledge, a new car... that is a car during its "break-in" period should not be left idling for more than 3 minutes as much as possible. For most cars produced after 1990, a 15 seconds warm-up is enough on a warm morning. On a slight chilly day... increase the time to about 30 seconds... and on a deadly cold morning... about 3 minutes.. or until you notice that the engine's sound is getting slightly smooth... but not until the rev comes below 1000rpm. Also, warming up time should be increased slightly more for larger engines... Now, is warming up necessary?? ABSOLUTELY!!! From basic knowledge of thermal expansion of matter, when a cold engine is made to rev fast like hell... some parts of the engine will get hotter faster than others and this causes uneven expansion, for example lets say... the piston head get hot and expand while the cylinder walls are not as hot... When this engine is made to pump, both the cylinder wall and piston head will wear down faster than necessary, eventually leading to poor gas mileage, loss of power and lots of frustration for the owner of the vehicle. "This book belongs to us, the fighters" |