DAYUAN Petrol Engine Compression Tester Kit 9pc — 3" Dual-Scale Gauge, 0–300 psi

The DAYUAN 9-piece Professional Petrol Engine Compression Tester Kit is a complete diagnostic set that measures cylinder pressure on petrol engines using a 3-inch dual-scale gauge and multiple adapters for broad vehicle compatibility.

This compact kit gathers everything a mechanic or DIYer needs to evaluate engine compression: a 0–300 psi / 0–20 bar gauge, threaded fittings for common spark plug sizes, quick-check rubber cones, pressure hoses with nozzles, and a fitted carry case. The tools are built for petrol engines in cars and motorcycles, allowing fast, repeatable pressure readings to help pinpoint worn rings, leaking valves, or head gasket issues.

How does the DAYUAN kit measure engine compression accurately?

The kit uses a 3" mechanical gauge with a dual color scale that displays both psi and bar for clear, immediate readings. A secure threaded connection or rubber cone ensures minimal leakage during cranking, which preserves accuracy across repeated tests.

• 3-inch gauge with 0–300 psi and 0–20 bar scales for clear visibility
• O-ring sealed male thread fittings to prevent pressure loss
• Flexible pressure tubes to route readings away from the engine bay

Which engines and spark plug types will this set work with?

Included adapters cover the most common petrol engine spark plug thread sizes and depths, making the kit suitable for many cars, light trucks, ATVs, and motorcycles. Quick-check rubber cone ends let you test compression when threading an adapter isn’t required or practical.

• Adapters: M10, M12, M14, M18 male threads for wide vehicle fitment
• Spark plug adapters: 14mm and 18mm included for typical spark plug ports
• Two rubber cone ends for fast checks on non-threaded or hard-to-reach ports

What components come in the kit and how are they organized?

The DAYUAN kit bundles the compression gauge, multiple threaded fittings, pressure hoses with rubber nozzles, two rubber cone ends, and secure spark plug adapters inside a molded carry case. The case keeps each piece accessible and protected for workshop or roadside use.

• Durable 3" dual-scale compression gauge mounted in the case
• Assorted male-thread adapters with O-ring seals for leak-proof connections
• Pressure tubes and rubber nozzles plus quick-check rubber cones
• Compact, specially designed carry case for transport and storage

How should I interpret results and use them safely?

Compare each cylinder’s peak pressure to the manufacturer’s specification; consistent low readings indicate ring or cylinder wear, while a big variance between cylinders can point to valve or head gasket leaks. Always follow engine shutoff, ignition disable, and crank-safety procedures before attaching the tester.

• Record peak psi/bar per cylinder and compare to service manual values
• Perform multiple cranking attempts for repeatable readings
• Disable ignition and fuel system before testing; follow safety precautions

Who is this for: The DAYUAN 9Pcs Professional Petrol Engine Compression Tester Kit is made for mechanics, home enthusiasts, and roadside technicians who need a reliable, portable compression testing solution. It suits workshops and mobile repair setups that service petrol engines across cars, light trucks, motorcycles, and small engines, offering clear gauges, broad adapter coverage, and organized storage for field or garage use.