Nozzle Opening Pressure Test
WARNING: This page does not describe the selected car, but rather 31 other vehicles, including the 2002 Saturn Vue, 2002 Pontiac Montana, 2002 Pontiac Aztek, 2002 Oldsmobile Silhouette, and 2002 Oldsmobile Bravada. However, it is still accessible from the selected car via links, so may be relevant.
WARNING:
DO NOT place your hands or arms near tip of nozzle when testing nozzles. High pressure atomized fuel spray from a nozzle has sufficient penetrating power to puncture flesh and destroy tissue. This may result in blood poisoning. Always enclose nozzle tip in a receptacle, preferably transparent, in order to contain spray.
NOTE:
Nozzle Opening Pressure Test should only be performed on vehicles with high mileage engines that have been overheated or on vehicles that pull heavy loads. False or inaccurate readings can occur if following tests are not performed to this criteria.
- Position a nozzle tester on a workbench.
- Install one nozzle on tester fitting.
- Place a container under nozzle that will deflect nozzle spray and absorb test fluid.
- Install 2 clear plastic hoses one inch (25.4 mm) long over leak-off fittings.
- Close shut-off valve at pressure gauge.
- Operate lever of nozzle tester repeatedly and briskly to fill and flush nozzle with test oil.
NOTE:
Each test should be considered independent of the others. For example, when checking opening pressure, DO NOT check for leakage. If all tests are satisfied, nozzle assembly can be reused. If any test is not satisfied, complete nozzle assembly must be replaced. When performing injection nozzle tests, use manufacturers instructions provided with Nozzle Tester (J 29075-B).
- Open shut-off valve at pressure gauge 1/4 turn.
- Depress tester lever slowly. Record pressure at which needle of pressure gauge stopped. Maximum observed pressure is opening pressure. Some nozzles may pop while other nozzles may drip down (this is not leakage).
- Opening pressure for used nozzles should not be less than lower limit of 1500 psi (105 bar) for naturally aspirated engines and 1700 psi (117 bar) for turbo-charged engines.
- Replace nozzles which that are less than lower limit.