When conducting a cylinder leakage test, Technician A says the piston must be at the top of the cylinder (TDC)when the test is being performed. Technician B says a reading of 0 percent leakage indicates the piston rings are worn or broken. Who is correct?

Question

Quizplus · Accepted Answer

Technician A is correct because for an accurate cylinder leakage test, the piston must be at top dead center (TDC) on the compression stroke to ensure the valves are closed. A reading of 0 percent leakage would actually indicate a perfectly sealed system, not worn or broken piston rings as Technician B suggests.

When Conducting a Cylinder Leakage Test, Technician a Says the Piston