Stop using impact guns on injector hold-down bolts

I pulled a set of injectors out of a Cummins ISX last week and three of the hold-down bolts were twisted almost to the breaking point. A torque wrench takes 30 seconds longer but saves you a $400 headache when one snaps off in the head. How many of you have seen this same mess?

2 comments

2 Comments

stellas562d ago

Yeah it's the same thing with people cranking down on oil pan bolts with a ratchet instead of a torque wrench. Nobody wants to take the extra minute until they're drilling out a broken bolt at 5pm on a Friday.

blairm352d ago

Yeah stellas56 hit it perfect with that "drilling out a broken bolt at 5pm on a Friday" bit. I actually read a tech bulletin from Cummins that said those ISX hold down bolts have a specific torque to yield spec and if you go past it even a little the metal gets weak and can snap later. I watched a guy at the shop next door learn the hard way last month. He used a pneumatic impact on the injector bolts and two of them twisted clean off on his test drive. Took him three hours to drill and extract them and the customer was not happy about the extra labor charge. It really is one of those things where being lazy for two seconds costs you a whole afternoon.