Engine/Transmission (1998.5 - 2002) Injector overflow question

[Texas Diesel]

What exactly is injector overflow? Every diesel I have ever had, has a low pressure return line to the tank from each injector. Even at idle there apprear to be some flow



I dont know if the HPCR has them.

 

[MCummings]

It's the fuel that's left over in the body after the injector pops off.



Other than that, that's all I know.



I've read about what that return line is for, but I suffer from CRS.



Merrick

 

[rweis]

I think the fuel in the injector body also is for lubrication of the injector body parts.



Bob Weis

 

[RJPotts]

The overflow line is there because when the plunger in the injector moves down there is a void at the top of the injector. Even though the tolerances inside are very tight, some fuel still gets to the top of the injector which is bad because without the overflow/return line the injector's internals could become hydraulically locked. That is the main reason for the return line. It is there for cooling and lubrication purposes also though as rweis and MCummings said.

-R. J.