Cummins ISL 400 HP

[Alex.isl400]

No, it makes no difference weather the exhaust brake is turned on or off. The only thing that causes the smoke is when I apply the brake with the brake pedal.
It smokes when I apply the brake weather the exhaust brake is turned on or not.
The way this exhaust brake is set up, when turned on, it’ll come on when ever I take my foot off the accelerator, or when going down a grade and the RV is trying to coast factor than the speed it’s set at, but that doesn’t cause the smoke issue either.

 

[Alex.isl400]

My isl400 started doing the same thing smoking while applying service brakes it would even choke out the motor most of the times so I did digging and unplugged the auxiliary brake wire from the head and no smoke or choking I don't get what's wrong with the engine brake why would it be doing that? Any help plz thanks

 

[Rich W.]

No, it makes no difference weather the exhaust brake is turned on or off. The only thing that causes the smoke is when I apply the brake with the brake pedal.
It smokes when I apply the brake weather the exhaust brake is turned on or not.
The way this exhaust brake is set up, when turned on, it’ll come on when ever I take my foot off the accelerator, or when going down a grade and the RV is trying to coast factor than the speed it’s set at, but that doesn’t cause the smoke issue either.

Ok re-reading this and given Alex’s experience, maybe your exhaust brake is sticking or over-actuating. Try disconnecting it as he did and see what happens. If thats it, a good cleaning and service as necessary of the exhaust brake will probably clear up the problem.

 

[JerryD]

Ok re-reading this and given Alex’s experience, maybe your exhaust brake is sticking or over-actuating. Try disconnecting it as he did and see what happens. If thats it, a good cleaning and service as necessary of the exhaust brake will probably clear up the problem.

No, when I apply the exhaust brake, the engine actually changed pitch and when I release the brake it goes back.

I’m also concerned that the ECM answer is a guess and it could be an expensive one. If they want to start swapping parts I would get an agreement in writing that there will be no charge if it doesn't solve the problem. Ive seen far too many posts on forums about people paying for unnecessary repairs and parts because the tech was guessing.

well it turned out, the Spartan service (Boarder Engine Rebuilding) in Mission Tx replaced the ECM $5K , cured the smoke issue.