When cylinders are chromium-plated, piston rings used in those cylinders must not be chromium-plated.

When cylinders are chromium-plated, piston rings used in those cylinders must not be chromium-plated.

• A. True
• B. False
• C. Not applicable
• D. Depends on model

Answer: (A)

The key idea is material compatibility at the ring–bore interface. A chromium-plated cylinder bore is extremely hard and very smooth to resist wear. If the piston rings are also chromium-plated, their mating surfaces can interact in a way that leads to poor seating, scuffing, or even flaking of the plating, which can contaminate oil and ruin the seal. To avoid those problems, non-chromium piston rings (typically plain steel or nitrided rings) are used with chrome-bore cylinders so the wear and sealing characteristics stay reliable. This rule is a general practice, not dependent on a specific model, so the statement is true.

The key idea is material compatibility at the ring–bore interface. A chromium-plated cylinder bore is extremely hard and very smooth to resist wear. If the piston rings are also chromium-plated, their mating surfaces can interact in a way that leads to poor seating, scuffing, or even flaking of the plating, which can contaminate oil and ruin the seal. To avoid those problems, non-chromium piston rings (typically plain steel or nitrided rings) are used with chrome-bore cylinders so the wear and sealing characteristics stay reliable. This rule is a general practice, not dependent on a specific model, so the statement is true.