VECKYJL TU-21 Dual-Gauge Cylinder Leak Down Tester Kit – 0–100 psi, 12/14mm Adapters for Cars, Trucks & Motorcycles

VECKYJL TU-21 is a dual-gauge cylinder leak down tester kit that finds and measures air leakage in 4-stroke engine cylinders to help locate worn rings, valves, head gaskets, or cracks. This compact diagnostic set combines a twin-gauge manifold, rugged hose and spark plug adaptors in a blow-molded case so mechanics and home technicians can quickly compare a suspect cylinder to a known-good cylinder. Rather than a simple compression reading, the TU-21 forces regulated air into the cylinder and quantifies where and how much air escapes, giving practical direction for repairs. Built from oil- and corrosion-resistant materials, the kit is designed for repeated shop use and tight-clearance engines in cars, trucks and motorcycles.

How does the TU-21 determine what’s wrong inside a cylinder?

The tester pressurizes a cylinder through a spark plug port and the dual gauges show applied pressure and percent leakage. By listening and observing where air exits (intake, exhaust, crankcase, or coolant passages), you can infer the damaged component without tearing the engine down first.

• Applies stable test pressure via AR2000 regulator (0–100 psi / 0–7 bar)
• Two 3" easy-read gauges for pressure and percent leakage
• Spark plug adapters (12mm & 14mm) fit common engines
• Leak location found by listening and watching for escaping air

What components are included and why do they matter?

The kit comes as a complete diagnostic package in a molded ABS case so every piece is protected and organized. Each included part is chosen to deliver repeatable, accurate tests and to fit a range of vehicle engines with minimal setup.

• Dual-gauge manifold with quick coupling and pressure release button
• Reinforced 480 mm hose for flexibility and pressure resistance
• 12 mm and 14 mm spark plug adapters for most passenger and light truck engines
• Detailed instruction manual and shock-absorbing rubber gauge cover

How durable and accurate is the TU-21 for regular shop use?

The TU-21 uses high-quality nylon resin and metal fittings engineered to resist oil and corrosion while keeping threads tight and leak-free. The gauges measure up to 100 psi with a stated accuracy around ±0.5%, making them suited for diagnostics where repeatability and clarity matter.

• Oil- and corrosion-resistant rubber and resin components
• Deep-thread metal fittings to prevent air loss at connections
• Reinforced hose designed to withstand torsion and temperature changes
• Acrylic gauge cover with anti-scratch coating for readability

Who is this for? The VECKYJL TU-21 leak down tester is aimed at professional mechanics, mobile technicians and knowledgeable DIYers who need a portable, accurate way to diagnose cylinder leakage without removing heads. It’s especially helpful when engine noise, poor performance or oil consumption suggest internal wear; the kit helps prioritize repairs by locating the leak source. Handle the instrument with care—this is a precision diagnostic tool rather than a basic compression tester—and follow the included instructions for best results.

FAQ

Q: Can the TU-21 be used on motorcycles and trucks?

A: Yes. The TU-21 fits most 4-stroke engines and includes 12mm and 14mm adapters to work with many motorcycles, cars and light trucks.

Q: Is this the same as a compression tester?

A: No. A leak down tester measures leakage percent and locates leaks; it complements but is different from a basic compression tester.