What is the valve clearance for Weichai engines?
4 Answers
Weichai intake valve clearance is 0.3mm, and exhaust valve clearance is 0.35mm. There are two common methods for checking and adjusting valve clearance: 1. Cylinder-by-cylinder adjustment method - After determining the piston position at compression top dead center according to the cylinder firing order, the intake and exhaust valve clearances of that cylinder can be adjusted; After adjustment, rotate the crankshaft and gradually adjust the valve clearances of other cylinders using this method. 2. Two-step adjustment method - Rotate the crankshaft to position the first cylinder piston at compression top dead center, align the flywheel mark with the inspection hole mark, then adjust valves 1, 2, 4, 5, 8, and 9. Then rotate the crankshaft one full turn to position the sixth cylinder piston at compression top dead center, and adjust valves 3, 6, 7, 10, 11, and 12.
As a seasoned mechanic with years of experience, I've encountered many issues with Weichai engines. Valve clearance is not something to guess—it depends on the specific model. Generally, for Weichai's WP series, the intake valve clearance is around 0.30mm to 0.35mm, while the exhaust valve is slightly larger at about 0.35mm. However, actual values may vary slightly depending on the engine's year and design. If the clearance is too large, the engine will sound like a drum and consume more fuel; if it's too small, the valves won't close properly, leading to weak power and long-term component damage. It's recommended to measure and adjust the clearance using a feeler gauge when the engine is cold. Car owners should keep an original manual handy to check the parameters—don't skimp on this small expense, as it brings peace of mind when driving.
I once experienced abnormal engine noise while driving my Weichai truck, and later found out it was due to incorrect valve clearance adjustment. Generally, the valve clearance for Weichai engines ranges between 0.30mm and 0.35mm, but there might be slight variations between different series like WP10 or WP12. Regular maintenance checks are essential, using professional tools for measurement—don’t attempt adjustments casually. Excessive clearance leads to loud noise and accelerated wear, while insufficient clearance can cause valve burning and air leakage. If you encounter similar issues, I recommend consulting a 4S shop or professional repair shop immediately and checking the manual for specific values. Addressing it early saves both time and money.
From an industry perspective, the valve clearance for Weichai engines should be determined based on the specific model, typically ranging between 0.30 to 0.35 mm for both intake and exhaust valves. Common issues include engine noise caused by excessive clearance, while insufficient clearance may lead to power loss and exhaust problems. Adjustment should be performed when the engine is cold, using precise measuring instruments. It is recommended that vehicle owners refer to the manual or entrust the task to authorized service centers to ensure accurate data and prevent subsequent damage.
