Cummins ISX High Oil Temp!

246F it’s when that solenoid should open and temperature start dropping to 238F then go up again to 246F and a cycle repeats. Your solenoid must stack closed

 

The problem is the oil cooler bypass thermostat. It doesn't open until the oil reaches 235 dev. F. No oil flows through the cooler until that temperature is hit. Cummins only offers one thermostat and it's too high a temp. Komatsu engine have a similar bypass system, but the stat opens at 185 dev. F.

 

Is the oil cooler bypass thermostat a 3690535? I'm dyno testing a qsx15 that has oil temperature problem and I'm testing it with a adaptor and a Komatsu thermostat. Under full load with the Cummins stat, oil temperature hit 234 deg. F. in the pan and 230 deg. F. In the oil gallery. First test with the adaptor and Komatsu thermostat, temperature was 230 deg. F. in the pan and 219 deg. F. in the oil gallery. Engine pulling full power for 1/2 hour. Still had some oil bypassing the oil cooler, building spacer to correct that problem and will test again today.

 

Ran engine at full power for 45 minute and had 226 deg. F. Oil pan and 216 deg. Oil gallery temp. Oil pressure increased from 35 psi to 38 psi. Lower temperature thermostat worked.

 

Im having same issue, i changed oil stat and oil temp still rises to 275F while water temp is at about 185F

 

Have the same problem on Cummings isx, oil temp goes from 230 to 250 and above only when I star going up hill, change the oil thermost and still have the same issue

 

Did you replace the oil thermostat that is in the front of the oil cooler housing or the oil bypass valve that is in the side of the housing. Asking in case the bypass valve was replaced (they have an updated one) thinking that is the thermostat

 

I have a 2014 isx 550 cm2350 that runs 250 all the time when loaded on a warm day. I was told that the thermostat (oil temp) is a 245* stat. Supposedly , you can get one for an earlier engine like a cm870 and swap it out by loosening alternator / ac bracket and accessing the round plug with a large Allen wrench. Earlier stats were like 225*? vs 245* on the newer engines. Yes, I know the newer engines are supposed to run hotter, but I never melted one that ran too cool.

 

I have a isx 12 Cummins my oil temperature reads 229 to 230 most of the time I replaced everything oil cooler oil thermostat is this a normal temperature?