The 6CTA8.3-M2 in my com. fishin boat is running 100 deg f hotter and the idle is lower.
I had the injectors checked and they were in specs.
Cracking injector lines reduces rpm in all cylinders.
The injector shop guy said it may be the pre inj. pump fuel pump (lift pump) going out.
Does this sound like what's going wrong? The motor water temp is fine ?? Thanks 4 reply.

 

How were the Injectors checked if you dont mind me asking?
Its Possible that its the Lift pump not providing enough fuel, thus creating a Lean State, which Can sometimes increase Temps. And would Def decrease Idle speed/ RPMs.

 

I pulled the injectors and took them to a injector shop. The guy has a pressure tester on a bench and said all were in specs. They have 6000 hours on them but are supposed to go at least 10k before a rebuild... It acts like it may have a real dirty filter, but all 3 are new.
If a cylinder was dead I think it would run rougher and show up when I cracked the lines.

I just talked to the guy who installed the motor and he says ignore the pyro and run it??

 

Well 100 degrees isnt really alot. but I would keep an eye on it if I were you. 300+ and you gettin pretty hot. Under a load is when it will show up the most... and your motor is toast!!

 

I had an aftercooler go out and run a small amount of water thru the motor...
The Cummins guy said more blowby and increased pyro is due to that...
I need to take another test drive and make sure I can get the full 2600 rpm out of it...
I only went to 2200 on the last run. Full rpm would mean a good lift pump...
Thanks for the reply...