check 3

If pressure reading exceeds 3 bars in the 1st test (see previous page), proceed as follows: - disconnect fuel return pipe (at point indicated by the arrow) and place in a container suitable for collecting the fuel. - operate the pump with the engine off, as described on the previous page, then read the presure level off the pressure gauge: a) if it reaches 3 bars, check fuel return line to tank because it is blocked or kinked; b) if it exceeds 3 bars, replace the pressure regulator because it is defective.

check 3

Checking pneumatic part of pressure regulator

- Remove electric lead and refit pump relay after replacing fuel return pipe to tank. Run engine at idle speed: pressure gauge reading should be 2.5 bar. If not, the air connection hose to the regulator manifold is defective or the regulator itself is defective and should be replaced.

Checking injector seal

To check for drips from the injectors, connect as described in first test (regulation pressure check) and operate pump with engine off. Once regulation pressure is reached, close fuel cock control lever (arrowed) (upstream of the pressure gauge) and simultaneously compress fuel return line to tank; use pliers for this purpose and avoid damage to the pipe This operation is necessary to tell the difference between an actual injector leak and an imperfect seal in the fuel pressure regulator reflux valve Then: - turn off the pump; - see whether the pressure remains constant for about 60 seconds once it stabilizes (i.e. drops slightly). If not, one or more of the injectors or a fitting must be leaking. - In this case, disconnect the fuel manifold from the inlet manifold while maintaining the connection to the pressure gauge. - Repeat the previous test, leaving the pressure gauge cock open. - 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.