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Just realized I've been overtorquing injector hold-downs for 15 years

Had a retired Cummins tech from Denver tell me to go 20 ft-lbs less on a 6.7 ISB last month and now I'm wondering how many threads I've messed up over the years, has anyone else had an old timer drop a simple tip that made you rethink everything?
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3 Comments
the_ryan
the_ryan1mo agoMost Upvoted
That torque spec probably came from a service manual written around a cold, dry, clean thread. Factory numbers assume perfect conditions. On a real engine with oil on the threads, carbon in the bore, or a used injector with a worn crush washer, that spec can be way too much. The old timers learned by feel because they had to. Sometimes the book number is just a starting point, not the final answer.
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jenny_coleman
Wait, wait wait. Are you seriously telling me that a used injector with a worn crush washer is a real thing people just deal with on a job? I thought you just cleaned the old one or got a new washer every time!
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caleb_thomas93
Sounds like I need to go apologize to every injector I've ever touched.
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