How to adjust the valve clearance of Weichai WP10?
3 Answers
Rotate the engine to the top dead center of cylinder 1 (align with the OT mark, the intake valve of cylinder 6 opens), adjust the intake valve clearance of cylinders 1, 2, and 4 to 0.4mm. Align the marking "1-6" on the outer edge of the flywheel, first adjust the exhaust valve clearance of cylinder 1 to 0.5mm, then adjust the brake clearance of cylinder 1 to 1.35mm. Align the marking "2-5" on the outer edge of the flywheel, first adjust the exhaust valve clearance of cylinder 5 to 0.5mm, then adjust the brake clearance of cylinder 5 to 1.35mm.
Adjusting the valve clearance on the Weichai WP10 isn't difficult, but it needs to be done step by step. I've done this several times, and the key is to operate on a cold engine to avoid burns from hot components. First, turn off the engine and let it cool for at least half an hour. Remove the valve cover, then slowly rotate the crankshaft with a wrench until the first cylinder reaches top dead center (TDC) on the compression stroke. Use a feeler gauge to measure each valve's clearance—the standard range is between 0.25 and 0.35 mm. If the clearance is off, loosen the lock nut, adjust the screw to the ideal value, and then retighten the nut to confirm. Be gentle when measuring; don’t force the feeler gauge to avoid damaging components. After finishing, reinstall the cover and restart the engine to check for abnormal noises. I recommend checking every 5,000 km or so, as excessive clearance increases fuel consumption and reduces engine power. I’ve seen neglected cases where increased noise led to costly overhauls—definitely not worth it. Keep specialized tools handy to save time and effort.
This job is quite interesting. As a car repair enthusiast, I've done it myself several times. You just need to prepare a feeler gauge, wrench, and gloves. Letting the engine cool overnight is more reliable. After lifting the valve cover and locating the key point of the first cylinder, measure the valve gaps one by one. Around 0.3 mm is the ideal value. When adjusting, don't rotate the screw too hard, as it's easy to strip the threads. After finishing, tighten the nut and test whether the gap is even. It's a bit of a technical job, but once you learn it, you can save a lot on repair costs. I recommend finding some video tutorials online to follow along; even beginners can get the hang of it. Remember, after adjustment, the engine runs smoother, with much less noise and more power. Regular checks are good for the engine's lifespan; I do it every six months to prevent problems.
