Community Forums

smlranger · 08-20-2013, 08:51 AM

Just curious what the average operating temp is for others with the ISL. I have the 425hp clean engine and my average temp at 70F ambient outside is running 182 - 185 on level road and up to 195 when climbing hills.

I am curious since my fan runs at full speed constantly (Danfoss fan controller is likely shot) and I want to make sure I am not running below the normal range for this engine.

Clayobx · 08-20-2013, 09:06 AM

I have the 450 ISL, pulling a Ford Edge at approx 5K. Just completed a 3K trip through the mountains, NY, VT, PA, etc. lot of climbing and being from FL lot of flat interstate travel. FYI, tranny ran 204 max, engine 203 f., max. The range was usually both at 199 to 200 in 90 degree plus temps. I have seen many conflicting post regarding engine temps. Our coach is just breaking in at 17K after a great year of travels. I hope this helps, your temps sound a little low?

JMonroe · 08-20-2013, 02:49 PM

I think the new DEF engines are tuned to run a bit warmer. Both our trans and engine temps will be within a few degrees of 200 most of the time.

Rich-n-Linda · 08-20-2013, 06:50 PM

My 400 HP ISL runs between 190 and 205 all the time.

smlranger · 08-20-2013, 06:59 PM

Thanks for all the feedback.

I decided to call Cummins Customer Service since I have gotten answers all over the board on this question.

Cummins said the T-stat on my particular engine (not DEF but their first generator of clean diesels which uses a diesel particulate filter in the exhaust) is set to open at 180 degrees. They said any temp above that is fine and the range I report (182 - 192) while at the low end, is OK.