Oil Cooler Pressure Testing

Introduction

The following is the factory procedure for pressure-testing the oil cooler element used on normally-aspirated 944s. If oil and water have mixed in your car and you are replacing the oil cooler seals, pressure-testing the element at the same time is a sound practice.

If you prefer not to set up the test rig, a radiator shop can perform this test with their existing equipment.

Tools

• Dust cap (23 mm or 1 inch)
• Hose clamp for dust cap
• Water container large enough to submerge the oil cooler
• Hose (1 inch) large enough to connect to the other oil cooler nozzle
• Compressed air supply
• Adapter to connect the air supply to the 1-inch hose

Testing

1. Install a dust cap with clamp on one of the oil cooler nozzles.
2. Connect a 1-inch hose to the other nozzle and, using adapters, connect the compressed air supply to the hose.
3. Submerge the oil cooler in a tank of water.
4. Pressurise the oil cooler to approximately 0.8 bar (12 psi).
5. Look for air bubbles emerging from the oil cooler. If bubbles are present, replace the cooler element.