Black smoke and running warm

[Derick thrappas]

Looking for advice cummins 5.9 factory reman long block 2020 350 hrs . Part time charter boat started running a little warm on second trip last weekend. Swapped gauge and problem stayed the same. I replaced the thermostats last yr with the 160* and they stayed nice and cool but now stbd is running almost 190* and has a little black smoke definitely more on the transom then port.   I cleaned strainers but before I dig to deep looking for suggestions possibly dirty air filter?? Both the r/g and fuel coolers were replaced this winter. What links more smoke and high temp? Too much fuel?

Topic

[Tony Athens]

As mentioned by Steve———–AFTERCOOLERS———————By far the highest maintenance parts on your engines

The exact proper service history of them is ??  

Post good pictures of your engines as installed–Need to see what you have. 

Be sure I see the turbo and wet exhaust connection/mixer      

[Steve Lewis]

DT,

Dark Smoke means lack of air.  That combined with some elevated coolant temps could point to a rather dirty aftercooler.  That is one of the very first items that the raw water gets to and if it is dirty on both the water and air sides that could be restricting the amount of air allowed into the intake and then the amount of water that makes it to the heat exchanger.  You are in Salt/Brackish water so you seem to be due for an Aftercooler service.  Ideally every 2-3 years when in salt.

Check out Tony’s Tips section and you will see an article named “Understanding Low Power Troubleshooting”. There is a section about Dark Smoke…….

 

[Author]

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