Roy Deeble, Joel post about exhaust brake is on to something after reading your last post.
What sounds like is happening exhaust brake is sticking and not in complete open mode.
This happening causes back pressure within the exhaust letting engine warm up faster.
Exhaust temperature reaches 120 DEG F light goes off ( air cylinder opens flap all the way ).
I have in past post mentions that engine exhaust brakes need TLC because of air cylinder
wear, flapper valve sticky, pivots points. Again the thing that makes this BAC forum so
good is everyone feed back on helping solve problems. Joel I do believe you bought the
answer to exhaust brake problem. Dave Atherton Retired Cat Mechanic
