Innova Compression Tester Kit 4-Piece (3612) — 2.5" Dual-Scale Dial, 300 PSI Capacity

The Innova 3612 Compression Tester Kit is a four-piece diagnostic set with a 2.5-inch dual-scale dial and three spark-plug adapters to measure cylinder compression up to 300 PSI.

If an engine is running rough, losing power, or burning oil, a compression test is one of the quickest ways to pinpoint internal mechanical issues. The Innova 3612 combines a clear Bourdon-tube dial, a 15-inch oil- and grease-resistant hose, and adapters for cars, motorcycles, ATVs and marine engines. It reads in both PSI and kPa and includes a side-release valve that speeds repeated measurements without disconnecting the hose.

How does this tool reveal piston, ring, or valve problems?

Compression testing compares the peak pressure of each cylinder to the rest of the engine. Low or inconsistent readings help you identify worn piston rings, leaking valves, or a compromised head gasket so you can decide on further testing or repairs.

• Large 2.5-inch dial with dual-calibrated scales (0–300 PSI and 0–2100 kPa) for easy reading.
• Accurate Bourdon-tube movement provides steady, repeatable pressure readings.
• 15-inch high-pressure rubber hose resists oil and grease for longer life in the workshop.

Will it fit my vehicle or small engine?

The kit includes commonly used adapters so it fits a wide range of engines, from passenger vehicles to power sports and marine machines. Adapters cover most spark plug sizes and the hose length and fittings are suitable for access in tighter engine bays.

• Includes 18mm and 14mm adapters for many cars and light trucks.
• 12mm adapter included for motorcycles, ATVs, snowmobiles and many outboard engines.
• Side-release valve lets you test multiple cylinders quickly without disconnecting.

How durable and accurate is the gauge for regular shop use?

The Innova 3612 is built with a robust brass fitting and a pressure-rated hose to withstand workshop conditions. The Bourdon-tube mechanism and color-coded dial reduce reading errors and the metal fittings help resist wear from oil and grime.

• Brass fittings deliver reliable connections and corrosion resistance.
• Oil- and grease-resistant rubber hose designed for repeated use in garages.
• Color-coded gauge scale speeds interpretation of normal vs. low readings.

How do I use it safely and get reliable numbers?

Follow basic engine test procedures: warm the engine, disable ignition and fuel, and crank the engine at normal cranking speed while watching the gauge. Take multiple readings per cylinder to confirm consistency and compare all cylinders to the factory specification.

• Warm engine to normal operating temperature for consistent compression values.
• Remove the spark plug, thread in the appropriate adapter, and tighten securely before cranking.
• Use the side-release valve to bleed the hose after each test and record peak pressure readings.

Who this tool is for: mechanics, mobile technicians, DIYers and small-engine owners who need a straightforward, dependable compression gauge to diagnose internal engine faults. It’s well suited for home garages and professional shops that service a variety of vehicles, from cars and light trucks to motorcycles, ATVs and marine engines. If you want a quick, visual way to spot low compression and narrow down repairs, the Innova 3612 offers the adapters and durable components to do that job reliably.