So why does everyone treat a torque wrench like it's optional on injectors?

Last month I was over at a shop in Amarillo helping a buddy swap injectors on a 6.7 Cummins. Three different guys there told me they just 'feel it' when tightening down the hold-down bolts. One guy said he's been doing it that way for 15 years. I checked the torque on his last job with my wrench and three of six were way under spec. We're talking 5-8 ft-lbs too low on some. That's how you get injector cup leaks and copper washers failing early. Never understood why people will drop $200 on a quality torque wrench and then leave it in the box. Who else has seen a come-back job caused by guess-torquing?

3 comments

3 Comments

the_brian16d ago

Man that crushed washer story hits close to home

val_ramirez16d ago

I had a customer bring his truck back three times for a rough idle after a DIY injector swap. He swore he torqued everything perfectly by feel. I pulled the hold-downs and checked them with my Snap-on wrench - two were at 15 ft-lbs and one was at 12. Spec was 20. The copper washer on that low one was already crushed sideways. Cost him another set of gaskets and a Saturday afternoon to redo it.

marybutler16d ago

Torqued perfectly by feel" - that's a good one. I've seen guys who can do a head gasket by feel and it comes out just right, but injector hold-downs ain't that job. Those little bolts fool you because they snug up quick but you need that real 20 pounds to crush the copper right. Fifteen and twelve is basically finger tight on those. Bet he learned his lesson though, nothing teaches like a Saturday wasted redoing gaskets.