• mobile+86 15900595263
  • email

How to Use A 27-PC Master Radiator Pressure Test Kit

One of the most depressing moments for car owners is during an engine cooling system breakdown. This heart-breaking trend has been persistent since automotive engines were invented. Probably, at one point of your driving experience, you may have encountered a case where your car engine loses coolant; making it hard to maintain the recommended engine temperatures.

On most occasions, it can be very difficult to tell where the problem is coming from, especially from the driver’s seat at normal driving speeds. At this point, while driving, you may have noticed that the level of your car’s coolant was lower as compared to when you started the engine. You may have encountered a similar problem, or maybe even worse.

This can turn out to be a daunting task especially if you can’t pinpoint exactly the cause of the problem. However, it then turns out that this only happened when the system was pressurized. This implies that the thermostat becomes loose during regular driving conditions. Even though you managed to get your car fully up to temp and had it idling; you still couldn’t get it to pressurize enough leaving you confused where the leak is coming from.

The good news is that you can determine exactly where the leak is coming from with the help of a Radiator Pressure Test Kit on. You don’t have to worry, as I have done the hard job and compiled a guide on how to use a 27-PC Master Radiator Pressure Test Kit.

How Much Does A Complete Kit Cost?

To replicate the conditions experienced before, you can use a Radiator Pressure Test Kit. Before I further delve into the details of how everything works, it’s important that I first inform you of the average price of a full kit. A full Kit ranges from US$100 – US$150. If you haven’t got yourself a kit, you can order one today on our website: https://www.sunbrightools.com/radiator-cup-tester-my-rpt10/ How fast you receive your package will depend on the shipping address provided.

The image above is an accurate reflection of how a Radiator Pressure Test Kit looks like. Included are several fittings and pressure Caps for various radiators and mixing models. There’s also a pressure Pump and a guide which provides clear guidance on what to use on a specific model. It’s a very rudimentary Kit but more than adequate for most cars. The process is very simple and can be done with the radiator still in the vehicle. If the radiator is out of the vehicle, you must ensure that you plug the upper and lower radiator hole openings. You can use rubber sleeves with hose clamps and PVC end Caps, all of which can easily be found on any hardware store.

Operating Instructions

Now that we have been well acquainted and you have your kit ready, we can delve deeper in the operational details.

  • First, before performing any kind of test on your cooling system, it’s of essence that you first test the pump by first pumping it a few times just to make sure that it’s working correctly. When testing, DO NOT pump over 20 PSI.
  • Second, while testing the cooling system during the initial stages of inspection, it’s very important that you always ensure that the force is applied straight into the pump rather than at an angle when pumping the pump handle. Doing so may result in pump leakage. To further illustrate the statement above you can check out the figure below.

  • Third, make sure the system cold and simmered down. It’s not advisable to perform the given tasks under high temperatures. You can choose to leave your car overnight without any disturbance and perform the exercise in the morning. If you ascertain that the temperatures are at the optimum range, you can proceed and open the radiator cap. If you’re not sure, then it’s better you keep off otherwise, you can get severe burns since the contents are usually under high pressure.

Leakage Test in the Cooling System

As we have seen previously, the Radiator Pressure Test Kit comes with a whole heap of different attachments. Depending on the model or make of the vehicle, it’s worth noting which tool you’ll mostly need. For example, tool number 6 will do well with the majority of Australian and European make vehicles. Find out which sort of radiator cap you have on your car and you’ll be set to go.

27-PC Master Radiator Pressure Test Kit

Another essential tool that’s worth taking note of is the temperature guide (#02, #03 & #04). This tool will enable you to determine the temperatures. Basically, the 27-PC Master Radiator Pressure Test Kit is a must-have tool in your workshop or at home. This will enable you to diagnose any coolant leaks at your own convenience.

1. Refer to the vehicle’s service manual for any specific radiator pressure testing instructions.

2. Have a clear look at the radiator cap. Every Radiator Cap will have a PSI or a BAR writing on it. Under any given kit, you’ll find different attachments of Radiator Caps. Check the guide to select the correct number for your application. In most cases, it’s often a solid cap dedicated to certain vehicle model types (Asian, Australian, and European, etc.)

3. Loosen the vehicle’s radiator cap slowly to relieve any excess pressure before removing the cap completely. NEVER OPEN THE SYSTEM WHILE HOT, as this may cause personal injury. If you happen to spot nicks on the radiator seal or if you happen to notice wear and tear, then the cap is probably not sealing properly. The best course of action, in this case, is to replace.

4. Select the proper adapter and configuration of the stationary seat accessories. Securely attach the adapter to the filler neck of the radiator or expansion tank.

5. Attach the quick connector of the hand pump onto the adapter. It should slip right on.

6. Grab your pressure pump and rapidly pump the hand pump handle using straight force as shown in figure 1 while watching the pressure gauge. Pressurize the radiator up to the optimal pressure only- DO NOT OVER PRESSURIZE THE RADIATOR. If your radiator has a 2BAR capacity (29.0075 PSI), you should ensure that the pressure does not exceed 2BAR. Ideal readings should range between 15 -20PSI (1.03-1.37 BAR).

  • Golds Steady Needle – If the gauge hand-holds at the same pressure number for 2 minutes, there are no serious leaks in the system.
  • Drops Slowly Needle – Indicates the presence of small leaks or seepage.
  • Drops Quickly Needle– Indicates serious leakage is present. In this case, you should put the pressure back up, get yourself a little torch and go hunting for the leakage. Depending on the model of the vehicle, you’ll notice a little drop happening somewhere. If the leakage is happening on the water pump for example, then it’s time for you to get yourself a new water pump.

1. Once the test is complete, release the air pressure by depressing the pressure release valve on the hand pump, then disconnect the quick coupler and adapter assembly. The pressure release sound signals that the tester is ready to be removed. If you happen to see water or any other coolant being expelled from the connector, do not be astounded. This normally happens at this stage of the process.

2. After completing the Radiator Test Process:

  • Keep the adaptor connected to the pump as you had set up while performing the actual test. Operate the pump several times to dissipate moisture and/or coolant that may have remained in the adaptor and pump.
  • Oil the hand pump in order to lubricate the piston and prevent corrosion and internal damage.

3. Store the radiator pressure tester kit in the carrying case and keep it in a clean, dry, safe location out of reach of children and other unauthorized persons.

Cooling System Pump


Leakage Test in the Original Radiator Cap

  1. Choose the correct radiator cap connector (5A or 5B) and correct steel radiator cap (#02, #03, or #04) for the correct vehicle being tested from the test kit.
  2. Fasten the original radiator cap to the radiator cap connector (5A or 5B)
  3. Fasten the steel radiator cap (#02, #03, or #04) from the test kit to the other end of the radiator cap connector (5A or 5B).
  4. Remove the hand pump assembly (#1) from the test kit and fasten the quick coupler at the end of the hose to the radiator cap (#02, #03, or #04) securely.

27-PC Master Radiator Pressure Test Kit

1. Operate the hand pump until reaching the pressure recommended by the vehicle manufacturer.

DO NOT OVER PRESSURIZE! Ideal readings should range between 15-20PSI (1.03-1.37BAR).

2. Check the pressure reading on the gauge immediately after reaching the vehicle manufacturer’s recommended pressure.

  • If the pressure drops, there is a leak in the radiator cap. In this case, you should put the pressure back up, get yourself a little torch and go hunting for the leakage. Depending on the model of the vehicle, you’ll notice a little drop happening somewhere. If the leakage is happening on the water pump for example, then it’s time for you to get yourself a new water pump.

3. After pressure testing is completed, press the release button on the quick coupler until the reading on the gauge reads 0. Remove the quick coupler from radiator cap and then remove the original radiator cap from the original radiator tap connector.

4. Discard the original radiator cap and replace with the new cap if there’s leaking or if it does not meet the manufacturer’s recommendations. If you have anti-fizz around the radiator cap when the motor is hot then it’s probably more likely that the seal is not sealing right.

Purging and Refilling the Cooling System


  1. Begin by creating a vacuum and draining the coolant from the radiator.
  2. Remove the purge and refill tool (#22) from the test kit and hang the tool in a convenient location under the hood with the hook provided.
  3. Chose the correct radiator cap for the vehicle being tested or the universal rubber radiator adapter (#23) from the test kit and install one of your choices on the cooling system opening. Fasten the quick coupler at the end of the hose on the purge and refill tool to the radiator cap securely. Connect the tool (#22) to the radiator filler neck and turn the rotor clockwise to fasten.
  4. Turn valve (#027) to the open position and valve (#26) to the closed position. This will create a vacuum in the cooling system. Keep creating the vacuum for 5-10 minutes.
  5. Connect air supply to the purge and refill tool (#22) and press the operating button until the pressure reaches 20-25hg (50- 60cmH) or 25-30hg (60-70 cmH).
  6. Turn valve (#27) to the closed position and press ON/OFF Switch (#28) off.

27-PC Master Radiator Pressure Test Kit


  1. Disconnect the shop airline and vacuum pump.
  2. Connect the coolant hose (#24A) to the coolant hose quick coupler (#29). Turn on the switch after the hose is submerged to a pre-mixed coolant.
  3. Ensure that the valve (#27) is in the closed position and that there is coolant in the coolant hose.
  4. Turn valve (#26) to the open position to allow the coolant to refill the cooling system.
  5. The refill is complete when the gauge reads D.
    NOTE: Please check the coolant level and add coolant whenever necessary to the proper levels.

This is a comprehensive and all-inclusive guide on using Radiator Pressure Test Kit. The above-covered areas are often the most essential with regard to coolant leaks. Nevertheless, different car model experience different problem. It is advisable you seek further guidance from your service provider in case the problem persists. Feel free to post your concern on the comment section and will gladly address them.

Leave a Reply

Notify of

The easy to use Wufoo form builder helps you make forms easy, fast, and fun.