Riello DB 4 LSM C13, Installation, Use And Maintenance Instructions

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12
4
Fuel supply
4.1 Pressure regulator
To calibrate cam 1): remove the gear-case, loosen screws 2), act on screw 3) until required eccentricity is obtained.
Turning the screw 3) to the left (+sign) eccentricity is increased, thus increasing the difference between nozzle maximum and min-
imum delivery.
Turning screw 3) to the right (- sign) eccentricity is reduced; thereby reducing the difference between nozzle maximum and mini-
mum delivery.
Every variation of the eccentricity may require a travel offset using nut and locknut 4).
NB.
• To obtain a correct calibration, cam 1) must operate over the travel range of the servo-motor as wider as possible; every vari-
ation of the servo-motor must be matched by a variation in pressure.
• Never give the variator piston a snug fit: stop ring determines the maximum travel.
• When the adjustment has been made, manually check that there is knocking between maximum and minimum and that max.
and min. pressures match pre-selected values as indicated on the delivery nozzle diagram.
If, at maximum nozzle delivery (maximum return pressure), pressure oscillations are detected on pressure gauge 6), slightly
reduce pressure until the oscillations are eliminated.
Fig. 13
Return Delivery
1
3
4 5
D8416
2
6