I have a pac brake on a 95 5.9 cummins turbo diesel. My exhaust temp went to 1200 degrees yesterday and i had no power. I can't tell if it's working or not. When the rod is in all the way, is the brake on or off.? I can get my exhaust temp down to about 500 if i drive under 60kph(40mph).

I'v only had this truck a short time. It has some sort of plate (fuel)and injectors. Also a rod on the side of the tranny thats hooked to a relay and some vacum lines (turbo boost) I think. A heavy duty torque converter. And who knows what else, but I'm still looking and finding something new every day.
It has 240000kms (150000miles)
Help Please, I don't think 1200 degrees is good--Could I have hurt anything?
Canuck101

 

If the Pac's cylinder rod was all the way down the butterfly should have been open, doesn't mean it was though. Did you check it with the engine running?
I've never seen it happen but perhaps the butterfly is broken inside the elbow in the closed position and explains your high egts. Best bet is to take it apart and see what's up. The guys at Pac are very good at taking care of problems, most often for free.

The rod and switch you see is connected to the throttle linkage so that the Pac butterfly only closes at idle.

1200° isn't too high if your probe is in the manifold but you don't want to go much higher.