How much is it to rebuild a cylinder?

The Bottom Line: Estimated Costs for Cylinder Rebuilding

The cost to rebuild a cylinder generally ranges from $500 to $1,500 per cylinder for automotive engines, while a single motorcycle cylinder can often be refreshed for between $300 and $800. These figures vary wildly based on whether you are doing a "top-end" refresh (rings and gaskets) or a full mechanical restoration involving boring, honing, and oversized pistons. If you perform the teardown yourself, you can save significantly on labor, which typically accounts for 60% to 70% of the total invoice.

Breakdown of Core Expenses

A cylinder rebuild is not a single transaction but a combination of parts, professional machining services, and intensive labor. To understand where your money goes, we must look at the specific requirements of the engine block and the piston assembly.

Machine Shop Services

Unless the cylinder walls are perfect, you will need a machine shop. Deglazing or a simple hone usually costs $30 to $60 per hole. However, if there is deep scoring, the shop must "bore" the cylinder to a larger diameter, which typically costs $75 to $150 per cylinder. For a high-performance motorcycle cylinder with a Nikasil coating, you cannot simply bore it; it must be stripped and re-plated, which can exceed $250 for a single bore.

Replacement Parts

Once the cylinder is prepped, you need new internals. A standard piston kit (piston, rings, wrist pin, and clips) ranges from $80 to $250. You must also factor in a complete head gasket set, which can cost $50 to $150 for a single-cylinder bike or over $300 for a multi-cylinder automotive V8 engine.

Labor: The Invisible Giant

The most significant variable is how the engine reaches the shop. If you drop off a bare engine block or a removed motorcycle cylinder jug, you pay only for the machining. If you drop off the entire vehicle, the mechanic must spend hours on disassembly.

• Automotive shop rates: $100 - $180 per hour.
• Motorcycle specialty shop rates: $90 - $150 per hour.

Removing a cylinder head and piston assembly on a modern car often takes 6 to 10 hours of labor. Reassembly, timing the engine, and testing adds another 8 to 12 hours. This is why a simple part failure can lead to a bill in the thousands.

Cost Comparison by Engine Type

Factors That Inflate the Price

Not all rebuilds are straightforward. Several technical factors can cause the price to skyrocket during the inspection phase:

• Cylinder Head Cracks: If the cylinder overheated, the head may be cracked. Testing (Magnafluxing) costs $50 - $100, but a new head can cost $500 - $1,200.
• Connecting Rod Damage: If a piston seized, the rod may be bent. Replacing a rod adds $100 - $300 plus the cost of balancing the crankshaft.
• Oversized Pistons: If you bore a motorcycle cylinder out, you must buy specific oversized pistons, which are sometimes more expensive than standard OEM parts.

DIY vs. Professional Rebuilds

If you have the tools and a service manual, a DIY rebuild of a motorcycle cylinder is a viable way to save roughly $500 in labor. You still need to pay the machine shop for the precision work, but you handle the "grease work." However, for modern cars with complex overhead cam timing and tight engine bays, the specialized tools required (torque angles, cam locks) often make a professional shop the safer, though more expensive, choice.

Before committing, always compare the rebuild cost to a "crate engine" or a low-mileage used engine. In many cases, if multiple cylinders are damaged, a full engine swap is cheaper than a high-quality rebuild.