SACA Pneumatic Troubleshooting (C-304) 2025 – 400 Free Practice Questions to Pass the Exam

When air is escaping from the cap end port of a fully retracted cylinder, it indicates that there is a problem with the piston seal. Specifically, the piston seal is designed to maintain pressure within the cylinder and prevent air from leaking out. If the seal is worn, damaged, or compromised in some way, it can fail to create a proper seal, allowing air to escape from the cap end port.

This situation often results in a reduction in the cylinder's efficiency and can lead to incomplete retraction or other operational issues. A worn piston seal can also cause increases in maintenance costs, as it may necessitate more frequent repairs or replacements to maintain the system's performance.

The other options, while related to pneumatic systems, would not typically cause air to escape from the cap end port in the specific context of a fully retracted cylinder. For instance, a faulty pressure relief valve would usually impact system pressure regulation but not specifically lead to this leaking scenario. Similarly, a blocked air filter could restrict airflow but wouldn’t typically result in air escaping from a specific port when a cylinder is retracted. A malfunctioning actuator would indicate broader operational issues rather than a specific leak from the cap end port. Thus, worn piston seals are the most direct cause of