1.If the fitting is too tight, the plunger sleeve and pump body will easily deform and break when serious.

2.Due to improper assembly or particle impurities inside,the parts may be stuck.

 

The pump must be replaced once it is deformed or cracked.

 

For the new pump,there might also plunger stuck happening for reasons:

Incorrect oil will also cause stuck for new pump.For example in the diesel oil used, the actual gel content is too large and the acidity is also too high. After debugging, a residual oil film will latch onto to the surface of the precision coupling parts of the injection pump. After installation, the stuck phenomenon will be generated.In the other hand,If the new oil injection pump is not properly stored, the package not strict, the damp and rust proof material damaged, and the dustproof cap of the oil pipe joint is damaged or lost, etc., it will also cause the stuck phenomenon.