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Why pressure test an engine cooling system?

Pressure testing is used to check for leaks in the cooling system and to test the radiator cap. The most common pressure tester is the hand-pump device with adaptors to fit different size caps and the filler neck of the radiator. Another style of pressure tester uses shop air connected to the coolant overflow hose. A third style has an adapter that replaces the radiator cap and allows a pressure or temperature probe to be inserted. Shop air or simply the pressure generated by the coolant system can be used to measure the pressure and check for leaks.
To test the system using a hand pump tester, make sure the radiator is full. Use the correct adaptor and connect it to the filler neck. Attach the pressure tester to the adaptor. Slowly apply pressure to the system up to the range of the system or the range shown on the radiator cap. The system should hold pressure for at least two minutes. If not, check for leaks in the system.
To test the radiator cap with the hand pump, attach the cap to the pump using the proper adaptor and operate the pump until the cap starts to release pressure. Note the reading on the cap to see if it is releasing at the proper pressure. Stop increasing the pressure. The cap should be able to hold this pressure for approximately one minute. If the cap releases early or late, or does not hold pressure, replace the cap.
To test the system using shop air, install the adapter with the pressure probe. Connect the shop air and increase the regulator setting to the pressure rating for that system. After the pressure is reached, shut off the shop air. The system should hold pressure for two minutes. If the pressure drops, then check the system for leaks.
If no external leaks are found, always consider the possibility of a failed head gasket allowing coolant leakage into either the cylinders or the oil passages.
When having your mobile A/C system professionally serviced, insist on proper repair procedures and quality replacement parts. Insist on recovery and recycling so that refrigerant can be reused and not released into the atmosphere.
You can E-mail us at macsworldwide@macsw.org or visit http://bit.ly/cf7az8 to find a Mobile Air Conditioning Society repair shop in your area. Visit http://bit.ly/9FxwTh to find out more about your car’s mobile A/C and engine cooling system.

0 responses to “Why pressure test an engine cooling system?”

  1. […] Why pressure test an engine cooling system? | Mobile Air … – Oct 04, 2010 · Pressure testing is used to check for leaks in the cooling system and to test the radiator cap. The most common pressure tester is the hand-pump device …… […]

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