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I have just completed rebuilding my 1999 7.3L diesel injectors. On about the 3rd injector I torqued the upper body and sent the needle through the bottom of the fuel nozzle. I figured I got the shim sitting on the needle in sideways or something so I continued rebuilding the rest and was very careful when putting the pieces back together. Then I sent the needle through the nozzle again on injector 8. Yes, the last one I had to complete. I carefully took that one back apart to see if I could determine the issue but found nothing unusual. Any ideas as to what might've happened? I have been stealing parts from a junk vehicle that my mother wrecked, my own Pick-n-Pull, as I call it, so I figured I'd use parts from my truck to fix the ones I broke so not a complete disaster but I'd like to know what the heck I've done wrong
I used an adapter/holder tool which I purchased along with my rebuild parts. The injector mounts into the tool and a pin holds the lower body in place. The tool is held by a vise on the workbench. The tool holds the injector so one can remove the upper injector body from the lower injector body. It is then used so one is able to torque the upper to lower bodies upon reassembly. The holder tool comes with a pin which fits into one of the holes in the lower injector body and that pin allows for disassembly and reassembly without spinning the whole injector..
During reassembly is when I had the issue of sending the needle through the tip and then I had a hard time removing the holding pin from the tool.
I think I must've set the pin too far into the injector and kept the internal parts from seating properly as I torqued the upper to 75 ft/lbs. As I neared the 75 ft/lbs mark I heard the loud pop and pieces went flying.
This is my best guess as to what led to my problems and could have cost $$'s if I hadn't had spares. This shows the whole set up. I have nothing against the tool but I am going to contact the company and suggest the mods; either a hole with a cotter pin or a slot around the pin with an E-type ring. Here is the holder/tool with the holding pin only slightly inserted. This shows how the pin comes through the holding block. There is no indication of how much to stick it through. I'm going to modify the pin with a hole and a cotter pin so that it can only be inserted just the right amount and NO more! This picture shows the needle protruding out of the bottom of the fuel nozzle. That took some force!
Imjector Nozzle Breaking When Rebuilding
