Also check your mechanical fan clutch, If they're dead/dying then the fan isn't being spun at the proper speed and can lead to the temp creeping up when sitting still.

 

but the question is if i changed :
-heat gauge sensor
-thermostat sensor
-thermostat
-flush radiator
-burp system
and the only way the temperature gauge goes down is when i turn the heater on
what can it be ?

 

My truck will run 180 solid since i removed the A/C evaporator core in front of the radiator but i have a problem where if its cold outside like 55 and under mine wont warm up the gauge will go 1 line above 100 and ive changed every part of the coolant system

 

Fan clutch or a bad radiator. When you flushed the radiator did you also flush the block and heater core?

 

i have an 88 wagoneer changed everthing temp sensor water pump ,thermostat fan clutch and still running hot ...i have some stress cracks in my bottle thinking im losing pressure so thats my next change....i just cant figure it out

 

no didn`t flush the heater core but im going to change the fan clutch tomorrow ill let you know

 

I had overheating problems when i had a dummy light gauge, swapped a ligit gauge in and found i was having a similar problem. Flush your coolant system and check the clutch. Fair warning you might not like what you find in your coolant system if you wheel alot i pushed about 2 lbs of sand a grit outa my system when i flushed it.

When all else fails you can toggle switch your fan, i did it to mine and it works great. Switch is on the dash and i just flip it when it hits about 200 and it runs fine (main purpose of the toggle fan is to be able to keep cool in low gear and 4lo when wheeling but works just as well on road as off as a solution)

 

id pull the thermostat back out. put it in a pan of water on your stove with a thermometer in it and make sure it opens at correct temperature. auto parts stores sell cheapest they can find. i went to oriellys 5 times in one day buying the same 193 thermostat. 2 didnt work at all. one opended at 215. another at 220. and then i got one that worked right

i recomend doing this to everyone

 

Case in point. How good do you think the quality control is on a thermostat that retails at 4.99?

 

also how do you check to see if your clutch on your fan is working fine?

 

Agreed never replace the thermostat with a lower stat or remove it completely, just fix the real reason why its overheating. Couple things overlooked, is your a/c condensor and raditor free of derbis? Its amazing what kind of stuff you can find stuck inbetween the radiator and condesnor blocking your airflow. Also something simple, how bout your fan shroud? Have one? Its there not just soo you don't lose a finger from the fan haha, it helps pull cool air through the radiator and to the engine. Also some helpful things to include to us is, when is it overheating? Highspeeds? Sitting at idle?

 

run your engine until it is normal operating temperature and turn the engine off. Go spin the mech fan by hand and if it freely spins its bad. if it has some grip to it then its probably ok.

Also guys if you have a blown head gasket on the closed system it can cause overheating. It causes combustion to enter the cooling system if its blown on a certain side of the gasket.

Clogged radiators, clogged heating cores, faulty thermostats, bad clutch fans, Aux fan not working, block clogged, hoses clogged, water pump clogged. All cause overheating. Check all of this, flush your system, make sure you have flow, make sure your fans work. Make sure you have the correct fluid. Water is not good. Causes rust and blockages.

 

The fan clutch is a +/-$35 routine maintenance replaceable item. Their efficiency slowly degrades the moment they are installed. If u don't know how old it is, replace it. The spin test is weak at best. The FSM test procedure is somewhat drawn out and involves drilling a small hole in the shroud, mounting a thermometer, measuring air temp thru the rad with the motor running, blah, blah, blah. Again, just replace it if u don't know how old it is.

 

My engine was running warm and I accidentally tangled my multimeter wire in the fan. I still have a multimeter.... it stopped the fan. Time for a new clutch? Lol.

 

....just 1 more way to use a multi-meter. LOL