What Happens If New Valves Are Not Lapped?
2 Answers
Not lapping new valves can lead to poor valve sealing, low cylinder pressure, and other consequences. How the Throttle Works: The throttle is a controllable valve that regulates air intake into the engine. After entering the intake manifold, the air mixes with gasoline to form a combustible mixture, which then ignites to perform work. Throttle Location: The throttle is connected to the air filter at the top and the engine block at the bottom, earning it the nickname "the throat of the car engine." Throttle Maintenance: The throttle requires periodic replacement, with the interval largely determined by factors such as air filter quality, oil quality, and driving conditions.
I once took a shortcut by skipping the valve seat grinding step when replacing new valves. At first, it didn't seem like a big deal, but within a week, serious issues emerged: the engine shook violently at idle, like an earthquake, and acceleration felt sluggish with no power when stepping on the gas. Fuel consumption also skyrocketed by nearly 20%. When the mechanic opened it up, it turned out the valves weren't sealing properly, causing compression leaks and incomplete combustion, with black smoke pouring out of the exhaust pipe. Over time, the valves could overheat, warp, or even burn out, leading to costly engine repairs. Since then, I've learned my lesson—never skip valve seat grinding when replacing valves, as small mistakes can ruin your ride. This step is absolutely non-negotiable during regular maintenance.
