MDE 16 Q5

Correct Answer: D. Blockage or restriction in the air start pipework

Explanation:
If the air start pipework is becoming extremely hot, it typically indicates that there is a blockage or restriction in the pipework. This can cause the air to become compressed and heated up excessively as it tries to pass through the obstruction. Insufficient air supply pressure (A) or air leaks (B) would not generally cause the pipework to become excessively hot, while excessive exhaust gas temperature (C) is more related to the exhaust system rather than the air start pipework.

Correct Answer: C. Check for and clear any obstructions in the pipework

Explanation:
If the air start pipework is excessively hot, checking for and clearing any obstructions is the appropriate immediate action. Obstructions can cause the air to become compressed and heated excessively. Increasing air pressure (A) or cooling the pipework (B) may not address the underlying issue, and reducing engine speed (D) does not directly resolve the problem with the hot pipework.

Correct Answer: A. Allow the pipework to cool before handling

Explanation:
Allowing the pipework to cool before handling is a crucial safety precaution to prevent burns or injuries. Using insulated gloves (B) might be necessary, but the priority is to let the pipework cool. Increasing air pressure (C) or shutting down the engine (D) may not be necessary as an immediate safety measure compared to allowing it to cool naturally.

Correct Answer: B. Damage to the pipework or surrounding components

Explanation:
Excessive heat in the air start pipework can cause thermal damage to the pipework and surrounding components. The high temperatures can lead to material degradation, potentially resulting in leaks or failure of the pipework. Improved starting performance (A) and increased efficiency (C) are not typical consequences of excessive heat, and reduced engine power output (D) is not directly related to the heat in the air start pipework.

Correct Answer: B. Ensure proper insulation of the pipework

Explanation:
Proper insulation of the air start pipework helps to minimize heat transfer and prevents the pipework from becoming excessively hot. Increasing air pressure (A) or reducing engine load (C) does not address the heat issue directly. Increasing cooling water flow (D) might help overall engine cooling but does not specifically target the hot air start pipework. Insulation is the most direct method to manage and minimize heat buildup in the pipework.