04 international 9200i. Doing 65 on the NJTP when I could feel something wrong. Get off the road and go straight to a shop. They diagnose my # 6 injector went bad but, when they opened it they found a rocker arm tip cracked off. All is repaired and running well now but would any of you know how or why the rocket arm cracked? Is it tied into the injector? Perhaps because I kept driving to the shop? I attached a pic as well.
how many miles on the truck? could be metal fatigue caused it to crack and break. then cause a misfire on #6 injector. you did good in bringing it to the shop in a timely manner.
835,000 miles, it has a cat C15 that was rebuilt at 700,000. Truck runs really well and this has been the only engine issue so far. Thanks for replying.
If the overhead adjustment isn't set periodically the valve train tightens up and rocker arms will break. I have mine set every 100,000 which is a tad overkill but I think of it as preventative maintainence not only does it need to be adjusted but the valve train also needs visually inspecting. Preferable if you aren't doing it yourself to have the same mechanic set it every time.
Your injector plunger stuck and broke the rocker in my opinion, either from heat or it came apart internally. The cam lobe raises rocker up and down onto spring plunger of injector, if injector failed something had to give and it happened to be the rocker. You lucky it stayed intact and didn't make it's way to the crank, it would have made a big hole.
