how to repair denso common rail injector-4.

STEP 2.2 – Solenoid & Solenoid Valve Assembly

Fit the half ball valve into the solenoid valve stem and ensure that the flat face of the half ball valve is visible and level with the stem. DO NOT INSERT THE VALVE STEM INTO THE VALVE SEAT IF YOU CAN SEE THE SPHERICAL PART OF THE HALF BALL VALVE (Fig 22). IT MUST BE THE FLAT SIDE (Fig 21).

The half ball valve should stay in the valve stem when turned over and inserted on the valve seat. Once the valve stem is in position ensure it is free by rotating it (Fig 23).

Place the fuel calibration shim on top of the injector (Fig 24)

Next, insert the solenoid spring shim and solenoid spring into the solenoid and carefully fit the solenoid onto the injector, ensuring that the spring seats in the centre of the valve and hand tighten. Once hand tight, tension the solenoid assembly to 10‐12 NM (Fig 25).

OVERTIGHTENING OF THE SOLENOID ASSEMBLY CAN HAVE AN ADVERSE AFFECT ON THE OPERATION OF THE INJECTOR AND MAY RESULT IN DAMAGE TO THE SOLENOID.

STEP 3.2 – Nozzle and Cap Nut Assembly

Re‐position the injector assembly in the jig with the solenoid towards the bottom.

Insert the command piston into the injector body with the main shank machined with grooves towards the solenoid end (Fig 26).

Next insert the nozzle opening pressure shim and the spring into the central injector bore and then insert the pressure spindle on top of the spring with the smaller diameter facing the nozzle needle (Fig 27.)

Insert the locating dowels into the sealing face and place the injector over them. Place the (new) cap nut over the nozzle and screw down until hand tight (Fig 28).

Ideally some kind of injector clamping rig should be used to unsure alignment of the nozzle, if you can find something or manufacture anything suitable to hold the body. The arrangement pictured below (Fig 29) features the Stanadyne Injector Aligning Tool (Part #29617). An injector aligning tool was not used in this exercise and no operational problems were experienced, however it would be better to use one if available to minimise the risk of misalignment or breaking the dowel pins.