Diesel Injector Fuel Injector 0445120254 Bosch

Inspection and repair of injector plunger sleeve

(1) Check the abrasion on the hole of the plunger sleeve of the fuel injector. If the injector has passed the tightness test on the tester, then the plunger sleeve is available. If the leakage is large, the plunger and plunger sleeve must be replaced.

(2) Use a high-power magnifying glass to check the burr, carbon accumulation and deformation in the measuring hole. When the metering hole is damaged, the fuel injector cannot work normally. Do not try to clean with steel wire, plug gauge, etc., should use solvent cleaning.

(3) Check the loosening of the fuel oil choke plug and whether there is a crack on the plunger sleeve. Check the surface of the injector plunger sleeve for damage and flatness on the continuous contact surface of the plunger sleeve (black belt area). Thoroughly clean and blow dry all oil film on plunger sleeve before bluing. Check flatness of flat surface with flat plate (preferably grinding plate) and "bluing agent". If damage or unevenness is found, it should be ground and repaired. Do not use emery cloth or wire brush on the contact surface between plunger sleeve and nozzle head.

(4) If the injector overheats, the sealing gasket between the plunger sleeve and the injector body may melt. The nozzle head tight cap will be loose. As a result, lubricating oil may be diluted, injector holes clogged, and injector sleeves or plungers damaged.

(5) The oil inlet and return holes on the large capacity plunger sleeve are about 1.27 ~ 1.65 mm higher than the oil holes on the standard plunger sleeve. Standard fuel injectors and large capacity fuel injectors cannot be mixed on the same diesel engine.