i have a 99 cherokee 126000 miles the problem im having is the engine does not want to warm up. i replaced the thermostat 3 times already. i can basically drive 40 miles and the truck doesnt warm up any ideas

 

forgot to mention its a 4.0

 

Have you felt the upper and lower rad hoses to see if the are hot.. Upper should be hotter than the lower.. Maybe your Coolant Temp Sensor is bad and thats why your not seeing it warm up.. The car will warm up in some way no matter what, so youll always have some kinda of reading on your Factory Gauge..

 

There are a few threads on this if you do a search...

Also, a lil more info might be useful...
What is warm to you?
Is there an internal/dash temp guage?

The other posts entail the sagas of replacing and "burping" the system. Supposedly, air pockets in the engine/water pump can cause the issues you're speaking of.

Again though, this ain't my area of expertise, so I'll refer you to the search engine to look for burping the collant system, or coolant system flush or fill... Possibly even look at "overheating" as a tag word, as people have to work on the same (coolant) system that you are.

Good-luck,
have fun!

 

ive burped the system the top radiator does seem pretty hot but do u think it could be the sending unit messed up i had to switch in between thermostat houseing when the old one cracked. i put a factory 195 thermostat in. usual temp i want it to run at is about 200-210

 

how cold is it wher you live at this time

 

its usually about low 30s in the morning then about 50 during the day and around mid 30s at night

 

does the heater get hot , if not try blocking part of the radiator from out side air like you see the tractor trailer rigs doing

 

Once the line on the gauge gets about two lines up above 100 it gets hot. i don;t know if this would effect it but i replaced the muffler with a straight pipe

 

There's no way that engine will not heat up unless the t-stat is frozen open.

When you say "no heat" do you mean the HEATER doesn't warm up the car or the engine does not get warm.

MHO, bad temp sender or plugged heater core or plugged t-stat.

 

the engine gets warm but what im trying to figure out why it takes so long. i drove 40 miles the other day straight high way and by the time i got home it wasnt at operationg temperatures according to the gauge and the antifreeze is like a s*^t brown color

 

take a plastic garbage bag and block the grill so no air can be sucked thru cooling the radiator and sit in side with it running and watch what happens

 

def. will give that a shot and just curious how could i get all of the s*^t brown coolant out of my coolant system

 

X2, The brown s**t is normal the only way to clear it out is a really good flush, running clean water through until you get clear water draining out.

 

remove hoses and thermostat and flush with water hose being its that cold out have fun with that lol