Valtra 6550 - Fuel Injection Pump

Boost control
9
10
To intake manifold
11
1
2
3
4
5
6
7
8
89
Model Code Page
22. Fuel system
1. 6. 1999
6000--8750 220 5
15. 5. 1996
Fuel injection pump
V almet 6000---8400 , 8750 and 8950 tractors have a
Bosc h---make injection pump which is an in---line pump
and its basic construction is similar on engines with the
different number of cylinders.
F u el injection pump
1. Oil filling plug
2. Governor control lever
3. Hand pump on fuel feed pump
4. Lubricating oil into injection pump
5. O --- r in g
6. Return of lubricating oil to engine
7. Drive gear
8. Type plate
9. Boost control (6800,
8750, 8950)
10. Forc ed---feed solenoid for starting
(6800, 8750, 8950)
11. Indicator plug for adjusting injection
timing (6800, 8750, 8950 + all latest
tractors, which have a new governor)
The fuel injection pump is flange mount ed and sealed by
one o---ring (5) in the timing gear casing. The injection
pump is driven from the crankshaft t hrough an idler gear.
The injection pump is connected to the engine force---feed
lubrication system through an external pipe (4). Lubricating
oilreturnstotheengineviathehole(6)atthefrontendof
the injection pump.
The fuel feed pressure which fills the high pressure pump
elements with fuel is created by a piston pump which is
attached to the side of the fuel injection pump. The piston
pump is driven fro m an eccentric on the camshaft of the
injection pump. The fuel feed pump supplies more fuel than
the injection pump needs. The excess fuel flows through
the overflow valve back to the fuel tank. The fuel cools the
injection pump and also takes any air bubbles with it back
to the tank.
Note! 6800, 8750 (SigmaPower) and 8950 (SigmaP ower)
tractors have a boost control (9), which is connected via a
hose to the engine intake manifold. The boost control
adjusts injected fuel amount to the cylinders according to
the s upercharging pressure in the engine intake manifold.
In addition, these tractors have a forced---feed solenoid for
starting (10) on the fuel injection pump, see page 223/9.
Adjusting injection timing on 6800, 8750 and 8950, see
page 223/8.