coolant problem need help

[dareksupra89]

I'll take a stab at this.
The temp going from 175 to 190 should be normal. I say should because I have no idea what these new Cummins temp is.
If your driving and the temp is going from 175 to 190 then back to 175 that is nothing more than the thermostat opening at around 185(guessing) and as the cold water rushes in the temp falls back to 175 then slowly goes back up.
On my CAT the temp runs 172 to 183. I replaced the factory 195 thermostats to 180.

As for 215 at while idling is the engine fan on or off?
If its off theres your problem. Lack of air flow thru the radiator.

 

[dareksupra89]

Ok thank you for your help

 

[Southern Fried]

Sounds like thermostat to me. Unfortunately, on ISX, it's a pain in the butt to get to. Before going through all that trouble, though, do a static pressure test on the radiator. Also, look at the front of the radiator itself. If it's coated with oil and dirt, it's plugged and you might need to replace it. Cleaning all that crap out of there is nearly impossible.

Good luck with it.

Not necessarily..... back when I drove logging trucks the rads used to clog up with dirt road junk (they used to oil the roads or put calcium on em to reduce dust). When this happened we washed them from inside out with a steam jenny with a degreaser. I've also done this on my mud bogger with a pressure washer with a good detergent.

Sometimes you have to repeat the process a couple of times, depending on how dirty the rad fins are. Remember.... spray detergent from the fan/engine side of the rad first, let it soak in good, then pressure wash from the same side. Front to back just packs the dirt and gets crap all over your belts/alternator,etc.