Test 2

Test 2

Testing maximum fuel feed pressure (or pump efficiency)

Same connections as previous test. - Close fuel cock lever (A); - operate the pump with the engine off, as described previously: pressure should not exceed 5 bar (pump pressure relief valve setting). Otherwise, replace the pump because it is defective. If pressure measured in test 1 (see previous page) exceeds 1.1 ± 0.1 bar proceed as follows: - disconnect fuel return pipe (at point (1) for connection to rigid fuel return line to pump) and place in a container suitable for collecting the fuel. - operate the fuel pump with engine idling, then take pressure reading off pressure gauge: a) if it reaches 1.1 ± 0.1 bar replace the fuel return pipe to the tank because it is blocked or kinked; b) if it exceeds 1.1 ± 0.1 bar replace the pressure regulator because it is defective.

Then: - turn off the pump; - see whether pressure remains constant for 60 seconds after stabilising (i.e. dropping slightly). - After supplying the pump with the engine off, look to see whether any of the injectors or connection sections are dripping. Replace any dripping injectors and/or repair the defective seal in the leaking joint.

Test 3

Checking injector seal

To check for drips from the injectors, connect as described in first test (regulation pressure check) and then operate the pump with the engine off. When the regulation pressure is reached, close control lever B so that fuel pressure and injection pressure is the same.