Find Coolant Leaks & Check System Pressure Before Replacing Parts

A vehicle returns to the workshop for the third time with a low coolant level. No obvious puddle appears underneath it & the temperature gauge behaves normally during a short idle test. Rather than replacing another component on suspicion, the technician needs a way to investigate whether the cooling system holds its specified pressure.

Sykes-Pickavant cooling system tools at Industrial Shed focus on that diagnostic challenge. The collection contains pressure-testing equipment for compatible passenger & heavy vehicles plus a cooling system thermometer for specified temperature checks. These tools are relevant to automotive mechanics, diesel technicians & fleet maintenance workshops investigating coolant loss, radiator leaks, pressure-cap problems or abnormal operating temperatures.

Three products make up the current range: the Sykes-Pickavant 331595 315 Series Cooling System Tester – Master, Sykes-Pickavant 331400 Cooling System Tester HGV & Sykes-Pickavant 031925 Cooling System Thermometer. Their different purposes make vehicle type, test connection & measurement requirements the most useful buying criteria.

A Cooling Fault Is Not Always a Failed Radiator

Coolant loss can originate from several areas, including hose connections, radiator seams, expansion tanks, water pump seals or other parts of the cooling circuit. Some faults become apparent only when the system is pressurised or reaches a particular operating temperature.

An overheating complaint also needs to be separated from a pressure-loss complaint. Restricted coolant circulation, thermostat operation, fan control & temperature-sensing faults may require different diagnostic methods.

Before selecting a test tool, identify the question the workshop needs to answer:

► Is coolant escaping externally? Inspect the system & use an approved pressure test where appropriate.
► Does the system retain its specified pressure? Monitor pressure behaviour under the manufacturer's test conditions.
► Is the radiator or expansion tank cap functioning correctly? Use suitable cap-testing equipment where the tester & adaptor support that operation.
► Is coolant temperature behaving as expected? Measure temperature using an appropriate instrument & compare it with the vehicle's specifications.
► Is the fault internal? Additional procedures may be needed to investigate combustion-gas entry, internal leakage or related mechanical concerns.

A pressure tester is useful evidence-gathering equipment, not a universal answer to every cooling-system fault.

What Are Sykes-Pickavant Cooling System Tools?

Cooling system service tools are instruments used to assess the pressure or temperature behaviour of compatible engine cooling circuits. They support fault investigation before repairs & can assist with prescribed checks after components have been replaced.

The current collection has two main functions.

Cooling System Pressure Testing

Pressure-testing equipment allows a technician to apply controlled pressure through a compatible connection, then observe the system according to the manufacturer's procedure. This can help reveal external leakage or an inability to retain pressure.

Testing must remain within the specified limits for the vehicle & equipment. Applying excessive pressure can damage components or create a new leak.

Coolant Temperature Measurement

A cooling system thermometer assists with temperature-related checks when used with compatible equipment & the correct procedure.

Temperature measurements may help technicians investigate thermostat behaviour, temperature-switch operation or other cooling-system concerns. The results need to be considered alongside the engine's operating conditions & manufacturer specifications.

The distinction matters: pressure testing investigates sealing integrity, while temperature measurement helps assess thermal behaviour.

Choose the Tester for the Vehicles You Service

331595: For Workshops Handling Different Vehicle Applications

The 315 Series Cooling System Tester Master Kit is designed to assist with locating internal & external cooling-system leaks across a range of compatible vehicles. Its master-kit configuration is intended for workshops needing more than a single test connection.

The key purchasing detail is the adaptor selection. Radiator necks, expansion tank connections & pressure-cap arrangements vary, so technicians should confirm that the included fittings suit the vehicles they service.

A broad kit is useful only when its adaptors match the workshop's actual requirements.

331400: For Heavy Vehicle Cooling Systems

The Cooling System Tester HGV is intended for heavy goods vehicle cooling-system diagnostics. Truck & commercial vehicle cooling circuits can differ substantially from passenger-car arrangements in their access, connections & system capacities.

Fleet workshops should check the relevant vehicle's test connection, specified pressure & operating procedure before using the equipment. An HGV designation does not establish compatibility with every truck, bus or piece of mobile machinery.

031925: For Temperature-Related Checks

The Cooling System Thermometer is listed for monitoring coolant temperature during compatible diagnostic procedures. Industrial Shed's product information identifies compatibility with Sykes-Pickavant 319 Series cooling system testers.

That compatibility detail is important because the thermometer should not be assumed to connect directly to either of the pressure testers listed in this collection. Confirm the required tester arrangement before ordering it as an accessory.

Where Cooling System Testing Makes a Difference

Slow Coolant Loss Without an Obvious Leak

Small leaks may leave residue around hose connections, radiator tanks or water pump housings without producing a large puddle. A suitable pressure test can assist with identifying leakage while the system is inspected.

Technicians should also examine the pressure cap & associated seals where the procedure requires it. A system that loses coolant is not necessarily suffering from a failed radiator.

Suspected Expansion Tank or Hose Failure

Plastic tanks, ageing hoses & connection points can deteriorate through repeated thermal cycling. Visual inspection may reveal cracks, staining or damaged fittings, while controlled pressure testing can provide further evidence.

Avoid increasing test pressure simply because a leak isn't immediately visible. The specified limit remains the maximum permitted by the procedure.

Heavy Vehicle Cooling Faults

Commercial vehicles may operate for extended periods under demanding thermal conditions. Cooling-system concerns can interrupt fleet schedules & may involve components that are difficult to inspect during normal operation.

An appropriate heavy vehicle pressure tester supports structured investigation of compatible systems. Access requirements, cooling circuit design & pressure specifications still need to be confirmed for each vehicle.

Checking a Repair Before Release

After replacing a leaking hose, radiator component or other cooling-system part, the workshop may need to verify the repair using an approved test procedure.

A satisfactory pressure test is useful, but it does not replace the remaining checks specified by the manufacturer. Coolant filling, air removal, operating temperature & leak inspection may all require separate attention.

For related mechanical service equipment, explore  Workshop Equipment.

Practical Pressure-Testing Procedure Considerations

Start With a Safe System

Never remove a pressure cap from a hot cooling system unless the manufacturer specifies a controlled procedure that can be performed safely. Pressurised hot coolant can cause severe burns.

Allow the system to reach the required test condition before connecting equipment.

Use the Correct Adaptor

An adaptor must seat correctly on the specified radiator neck or expansion tank connection. Poor fitment can create a false pressure-loss indication or damage the connection.

Check seals, threads & mating surfaces before applying pressure.

Respect the Test Pressure

Follow the vehicle manufacturer's specified pressure limit & the tester's operating instructions. More pressure does not make a test more accurate.

Inspect While Monitoring

Observe accessible hoses, joints, tanks & other likely leakage points while the test is underway. A pressure drop indicates a concern requiring investigation but does not automatically identify its location.

Separate Pressure Faults From Temperature Faults

A system may hold pressure yet still overheat because of circulation, control or other operating problems. Use suitable temperature measurements & additional diagnostic procedures where required.

Document the Result

Recording the test conditions, pressure behaviour & observed leakage helps workshops compare findings before & after repair. For fleet maintenance, these records can also support future fault investigations.

Broader measurement equipment is available through  Testing & Measurement Tools, while  Pliers offers related options for suitable hose-clamp & component-handling tasks.