What is a valve seat cutter used for?

A valve seat cutter is specifically designed for resurfacing the valve seat area in the engine's cylinder head. This tool is used when the valve seats become worn or damaged due to normal wear and tear, sealing issues, or improper valve operation. By using the valve seat cutter, a mechanic can create a smooth and proper angle on the valve seat, ensuring a tight seal when the valve shuts against it. This is crucial for maintaining optimal compression ratios and efficient engine performance.

The other options relate to different tasks in engine maintenance. Measuring fuel pressure involves using a fuel pressure gauge, not a valve seat cutter. Cleaning valve ports typically requires brushes or other cleaning tools suited for that purpose. Installing valve seals is done using specific seal installation tools, separate from the function of a valve seat cutter. Thus, the function of a valve seat cutter strictly pertains to resurfacing damaged metal on the valve seats.