Methods to Prevent Cylinder Block and Cylinder Head Cracks

    Cracks in cylinder blocks and heads result from poor design, material defects, manufacturing flaws, or improper operation and maintenance. From a usage perspective, preventive measures include:

    (1) Avoid prolonged engine overloading, which induces excessive thermal stress.

    (2) Never add cold water to an overheated engine. If coolant is low during operation, wait until the engine cools before refilling. Always fill the cooling system before startup to prevent dry running followed by sudden cooling.

    (3) Regularly remove scale from water jackets. Scale buildup reduces flow area and impairs heat transfer—especially between cylinders and around valve seats—leading to localized overheating and cracking.

    (4) After startup, avoid immediate high-speed operation. Rapid crankshaft vibration increases block stress, risking cracks at weak points.

    (5) Operate the accelerator pedal smoothly. Avoid abrupt throttle movements. During acceleration, open the throttle neither too quickly nor too slowly. Use the pedal to maintain optimal engine load and avoid sustained high RPM or overload conditions.

    (6) In freezing weather, drain coolant when parking outdoors overnight. Preheat with warm water before cold starts. For temporary stops exceeding 2 hours, drain coolant completely. If antifreeze meeting specifications is used, draining is unnecessary—but periodic engine runs may be needed to maintain temperature.

(Source: Mechanical Experts Network)