Draper Expert Commercial Vehicle Diesel Compression Test Kit (13 Piece)

Precise Diesel Compression Testing for Commercial Vehicles

Low compression is one of the most common causes of hard starting, excessive smoke, poor power output and high fuel consumption in diesel engines. Identifying it quickly and accurately — before it becomes a costly engine failure — requires the right tool for the job. The Draper Expert CTED1-E Diesel Compression Test Kit is purpose-built for commercial vehicle applications, delivering professional-grade results across a wide range of diesel engines.

Whether you're working on light commercial vans, trucks, buses or agricultural machinery, this 13-piece kit provides everything needed to conduct a thorough compression test on both direct injection (DI) and indirect injection (IDI) diesel systems.

Dual-Reading Gauge with Maximum Visibility and Protection

At the heart of this kit is a 63mm diameter dual-reading pressure gauge calibrated from 0–1000psi and 0–70bar. The large gauge face ensures clear, accurate readings even in poorly lit workshop conditions, while simultaneous psi and bar scales mean results can be recorded in whichever unit your service data requires — with no need for manual conversion.

The gauge is encased in a heavy duty rubber protector, shielding it from the knocks, drops and general workshop abuse that precision instruments inevitably face in commercial vehicle environments. It's a detail that speaks directly to the realities of daily professional use.

Anti-Kink Hose for Reliable, Durable Connection

The 380mm flexible hose connects the gauge to the engine's glow plug bore, and features anti-kink coils at both ends — a practical engineering choice that significantly extends hose life by preventing the stress fractures and internal restrictions that develop at the most vulnerable points of an unprotected hose. The result is a more reliable seal, more consistent readings and a longer-lived tool.

Integrated Safety and Accuracy Features

The kit incorporates two important valve systems that together ensure both safe operation and measurement integrity. The spring-loaded pressure relief valve allows you to safely release built-up pressure at the gauge after testing, eliminating the need to unscrew the adaptor from a pressurised hose. The integrated Schrader one-way valve system ensures that pressure is held accurately at the gauge between cylinder firing strokes, giving you a stable, readable peak compression figure rather than a fluctuating needle.

Comprehensive 13-Piece Adaptor Set

Commercial diesel engines vary enormously in their glow plug thread specifications — which is why the CTED1-E comes supplied with an extensive range of adaptors and fittings to maximise compatibility across vehicle makes and models:

• 1 x 63mm diameter pressure gauge
• 1 x 380mm flexible hose
• 1 x Threaded dummy glow plug
• 1 x Right-angled hose adaptor
• 1 x Clamping bracket
• 3 x Dummy glow plugs (various sizes)
• 5 x Adaptor sleeves
• 1 x Assorted sealing washers

The right-angled hose adaptor is particularly valuable when glow plug access is restricted by surrounding engine components — a common challenge on modern commercial diesel engines with complex layouts.

Organised Storage in a Plastic Carry Case

All 13 components are supplied in a fitted plastic storage case, keeping every adaptor, sleeve and washer accounted for and protected between uses. Nothing rolls around a tool drawer or gets lost at the bottom of a bag — a small but significant benefit when working on time-critical commercial vehicle diagnostics.

Key Features & Benefits

• Direct and indirect injection compatibility — Wide application coverage across commercial diesel engine types
• 0–1000psi / 0–70bar dual reading gauge — Simultaneous psi and bar scales; no manual conversion required
• 63mm gauge diameter — Large face for clear readings in all workshop conditions
• Heavy duty rubber gauge protector — Professional durability for daily workshop use
• Anti-kink coils at both hose ends — Extends hose life and maintains a reliable seal
• Spring-loaded pressure relief valve — Safe, controlled pressure release after testing
• Schrader one-way valve system — Holds peak pressure accurately for a stable gauge reading
• Right-angled hose adaptor — Access restricted glow plug locations on complex engine layouts
• 13-piece adaptor set — Broad compatibility across commercial vehicle makes and models
• Plastic storage case included — All components organised and protected

Who Is It For?

The Draper Expert CTED1-E is designed for professional commercial vehicle technicians, diesel specialists and fleet workshop engineers who need a reliable, comprehensive compression testing solution for trucks, vans, buses and agricultural machinery. The wide adaptor range and robust construction make it equally well suited to independent workshops handling a varied commercial vehicle pairing as to dedicated fleet maintenance operations.

Technical Specifications

• 13-piece diesel compression test kit for commercial vehicles — trucks, vans, buses and agricultural machinery
• Compatible with direct and indirect fuel injection diesel systems
• Dual-reading gauge 0–1000psi / 0–70bar with 63mm face and heavy duty rubber protector
• 380mm flexible hose with anti-kink coils at both ends for durability and reliable sealing
• Spring-loaded pressure relief valve and Schrader one-way valve for safe, accurate readings
• Right-angled adaptor for restricted glow plug access on complex engine layouts
• Includes 3 dummy glow plugs, 5 adaptor sleeves and assorted sealing washers
• Supplied in a fitted plastic storage case — all components organised and protected
• Product Code: CTED1-E | Brand: Draper Expert

Q: What vehicles is the CTED1-E compatible with? The kit is designed for commercial vehicles including light commercial vans, trucks, buses and agricultural machinery fitted with diesel engines using either direct injection (DI) or indirect injection (IDI) fuel systems. The 13-piece adaptor set covers a wide range of glow plug thread specifications across common commercial vehicle makes and models.

Q: What is the difference between direct and indirect injection diesel engines? Direct injection diesel engines inject fuel directly into the combustion chamber above the piston, while indirect injection engines inject fuel into a pre-chamber or swirl chamber adjacent to the main combustion chamber. Both require different testing approaches and adaptor configurations — which is why the CTED1-E is specifically designed to accommodate both systems.

Q: Why does the gauge have both psi and bar scales? Diesel engine service data is published in different units depending on the vehicle manufacturer and country of origin. Having both psi and bar scales on the same gauge face means you can read directly against whichever unit your workshop data uses, without needing to carry out manual unit conversions that can introduce errors.

Q: What does the Schrader one-way valve do? The Schrader one-way valve holds the peak pressure reading at the gauge between each compression stroke, preventing the needle from falling back between firings. This gives you a stable, accurate peak compression figure rather than a rapidly fluctuating needle, making readings easier to record and compare across cylinders.

Q: How do I safely release pressure after testing? The kit features a spring-loaded pressure relief valve that allows you to bleed off accumulated pressure at the gauge in a controlled manner before disconnecting the hose from the engine. This prevents the sudden, potentially dangerous release of compressed air that would otherwise occur when the adaptor is unscrewed from a pressurised bore.

Q: What is included in the kit? The 13-piece kit includes: 1 x 63mm pressure gauge, 1 x 380mm flexible hose, 1 x threaded dummy glow plug, 1 x right-angled hose adaptor, 1 x clamping bracket, 3 x dummy glow plugs, 5 x adaptor sleeves, and 1 x assorted sealing washers — all supplied in a plastic storage case.