Fuel injection pump

A fuel injection pump comprising: a rotatable cam; a drive shaft (14) for transmitting a rotational force to said rotatable cam (17); at least two fuel pressure chambers (30) for pressurizing fuel; at least two pressure feed fuel passages (32, 33, 34, 62, 72) for transmitting fuel pressurized in said respective fuel pressure chambers (30); a moving member (20) for reciprocating according to a rotation of said cam (17) to pressurize fuel in said fuel pressure chambers (30) and to transmit said pressurized fuel to said pressure feed fuel passages (32, 33, 34, 62, 72); at least two cylinder heads (12, 13) and forming said respective fuel pressure chambers (30) there-inside; a main housing (11) made of aluminium for rotatably supporting said drive shaft (14), wherein; each one of said pressure feed fuel passages (32, 33, 34, 62, 72) includes a communication port (32a) for communicating with said fuel pressure chamber; and each one of said pressure feed fuel passages (32, 33, 34, 62, 72) includes a fuel outlet; wherein said pressure feed fuel passages (32, 33, 34, 62, 72) are formed in said cylinder heads, respectively, and said cylinder heads are made of iron, wherein an electromagnetic valve (55) for adjusting a fuel amount is attached to the main housing (11), and wherein the fuel from the electromagnetic valve (55) is introduced to the fuel pressure chamber (30) through a fuel passage (53) formed in the main housing (11).