Question for diesel mechanics with experience?
Best answer: Some of it just comes from experience, BUT... Pretty much ANY shop that does work on commercial vehicles WILL have maintenance manuals and reference books with all the technical information you would need to do your job.
You will have manuals. For mechanics not working for a company, a lot of that info is available online. A friend of my oldest son bought a Cat 320C. One of the hydraulic cylinders was leaking. They took it apart and they found online that the nut on the end of the cylinder required 1400 ft lbs. The nut was 3 3/4" across the flats. I drew up a wrench for it and cut it out on the CNC plasma table. They got it to about 4000 ft lbs before the wrench started to fail.
Hi No it doesn't work like that you learn from doing apprenticeships only none of this hands on and doing the job. Time to get a grip here sunshine they are not going to let you loose with expensive machinery till they are sure you would not do anything stupid or silly. learning involves some classroom work as it does with most engineering jobs. so they need to be sure you are capable of dealing with tools and machinery.
If you think you are going to be torquing alot of fasteners think again. You will know how much torque to give fasteners by their size. Snap one and guess who gets to fix it. Torque is for engine interiors. Everything else is just tight. And yes there will be loads of info from the manufacturer. Any and more than you need.