z Valve spring inclination Use a surface plate and a square to measure the valve spring inclination. If the measured value exceeds the specified limit, the valve spring must be replaced. z Valve spring tension Use a spring tester to measure the valve spring tension if the measured value is less than the specified limit, the valve spring must be replaced. Spring tester DL06 Diesel Engine Disassembly and Reassembly of Major Components 75 Spring free length Standard Intake valve & Exhaust valve 53.4 mm Standard Limit Valve spring inclination 1.4 mm or less 2.0 mm Set Length Spring force Limit Intake and exhaust valve 39.4 mm 28.8 kg ±2 kg 29.67 mm 50 kg ±2 kg