#1 - Is improperly hosed fuel return from individual injectors. The fuel is used for lubrication of the moving parts in the nozzle and passes from the high pressure side past the pintle out of each injector.
#2 - Is one of the high pressure fuel lines running 1500-2000psi fuel pressure pulses to the injector. Fuel is pushed in one end by the injection pump #9 and comes out of the injector nozzle assy number 3 into the prechamber inside the head.
#3 - the injector nozzle holder assy. It breaks the fuel stream into an atomized pattern prepared for combustion in the prechamber.
#4 - This is the aneroid for the injection pump. It is an evacuated chamber attached to the governor mechanism for fuel control Its purpose is changing fuel mixture for altitude differences on non turbos and for boost enrichment on turbos.
#5 - The vacuum supply line from the vacuum pump to the vacuum assisted power brake booster.
#6 - The main fuel filter
#7 - The inline prefilter. It supplies fuel from the tank to the feed pump which it is attached to. It keeps the rocks out.
#8 - The return fuel line. This one looks like a piece of hose. The proper one is swollen in the middle to absorb pulses and dampen noise.
#9 - the injection pump
Bosch Master, ASE Master, L1
33 years MB technician