TM 5-3810-300-24&P-3
2.4
FUEL MANIFOLD
This provided a smooth sealing surface on the nut and the
The fuel injectors are supplied with fuel oil through pipes
copper washer was eliminated.
However, a one piece
connected to the fuel inlet manifold. Excess fuel oil is returned
connector which incorporated a nylon insert replaced the
to the fuel tank from the fuel injectors through pipes connected
former connector and nut. When the connector is installed,
to the fuel outlet manifold.
the nylon insert effects a complete seal between the threads of
the connector and the cylinder head.
The fuel inlet and outlet manifolds are an integral part of the
current cylinder heads (Fig. I). Since there are inlet and outlet
A special fitting with a restricted opening is used in the fuel
passages provided opposite each injector position in the side
outlet manifold to maintain the proper pressure within the fuel
of the head as well as at each end, greater flexibility is
system. Refer to Section 13.2 for the size of restriction used.
permitted in the installation of the fuel lines to the fuel
manifolds. The fuel passages are identified by the words "IN"
(top manifold) and "OUT" (bottom manifold) cast in several
Service
places in the side of the cylinder head.
When replacing a former cylinder head equipped with external
The fuel manifold connectors are assembled to the integral
fuel manifolds by a current cylinder head, discard the old fuel
fuel manifold cylinder head, using special steel sealing
manifolds and connectors.
washers, and tightened to 40-45 lb-ft torque.
A service cylinder head includes the new shorter fuel
The former external fuel manifolds were attached to the side of
connectors and the steel sealing washers. The current and
the cylinder head and locked in position by fuel connectors
former fuel connectors are not interchangeable. A length of
which set in tapered seats in the fuel manifold tee connectors
flexible hose and two hose fittings are also provided. Since
the fuel inlet can be located at any one of the inlet passages in
the side of the head, the flexible hose can be cut to the
The fuel manifold connectors used with the former external
required length for connecting the fuel filter to the fuel inlet
fuel manifolds were assembled to the cylinder head with a
manifold.
copper sealing washer and a lock nut which incorporated a
threaded fibre insert (Fig. 3). Later, an unthreaded fibre insert
The direction of flow of the fuel will, in most cases, be reversed
was used and the nut was installed with the fibre end down.
when replacing a cylinder head with the external fuel manifolds
Threads were cut into the insert when the nut was assembled
by one with the integral manifolds. Therefore, replace the
to the connector and provided a more effective seal against
filters before the injectors are reinstalled in the replacement
leakage of lubricating oil to the outside of the cylinder head. In
head. Otherwise, damage to the injectors will result due to
a later change, the staking operation, which secured the insert
foreign particles in the filter entering the injector.
in place, was omitted from the nut.
Fig. 1 - Cylinder Head with Integral Fuel Manifolds
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