Thermostat?

[onebadapple]

Hello! ‘15 CM 2350 101 450 hp. For the last couple weeks when I cold start it, it is not warming up like it was. Even the oil temp is warming faster than the coolant. Once off and running, everything seems fine. When stopped for a bit in the cold (single digit and -temps) it gets a little below the 180° where it didn’t before. I also use a winter front with adjustable blockage. Ok, my old school logic is saying I need to replace the thermostat. Well, being fairly new to an ISX, is there anything else I should be looking at while I’m replacing the thermostat?

Thanks!!!

[elez1995]

if possible check coolant temperature sensor. when cold, sensor should read about what the ambient temperature is. it can also be checked with infrared gun. it also is checked with voltmeter by measuring resistance.

then check fan, fan should not be working below 200F.
if fan does not operates below 200f then you should check thermostat.

first you check thermostat for leaking
{there is a} guide from quickserve how to check for leak.

[tree98]

(02-19-2022 )elez1995 Wrote:  then check fan, fan should not be working below 200F.
if fan does not operates below 200f then you should check thermostat.

Just remember the truck must be completely aired up for this to apply.