?????thermostat!!!!!

[PKLgreenJeepZ]

1058653

i have a 95 wrangler rio and i dont thins the temp gague has done this befor but it usually takes 20 min for it to get up to 210 and then stays there untill it cools down but today i was driving and it went up to 210 quite quickly porbly bout 5- 10min and it went to 210 then back to 150 back up then back down. is this normal or will i need a new thermostat? :-? [addsig]

 

[far_right]

1058655

thats what mine does too.....[addsig]

 

[dingus]

1058660

mine does that too... when it sits still, and warms up, it gets up to pretty close to 210* (i have a 180* thermostat and a new radiator) then once i start driving (and the air passing by the fins on the radiator cools it down) it drops to 150* or so...[addsig]

 

[MORGSTER]

1058680

The design of a thermostat is to keep the system closed until the water reaches the desired temperature and then opens to maintain that temperature ie: 160, 180, 190degrees ect. (Speed at which this happens depends on your climate, (sunny and hot =faster / cold and snow = slower). (For example in this case 180 degrees) Once the Jeep is running it won't go below 180. (The thermostat would close again until the water returns to above 180 degrees) Thermostats are prone to sticking, usually if the internal system is dirty or hard water has been used and corrosion occurs.
I had a with my 4.2 YJ where my temperature gage would fluctuate and sometimes run hotter than I wanted. I replaced the thermostat, radiator, water pump, coolant, checked connections and grounds and it still did the same.
Eventually solved, it was the temperature sender. Replaced it for about $8.00 at my local auto parts store.
[addsig]

 

[MORGSTER]

1058682

Note: If your system were operating correctly the temprature would only fall below the thermostats setting (For example 180 degrees) for a very short time. Usually this happens when the thermostat first opens after the Jeep has cooled down and the water is now run through the radiator that has cooler water inside. The thermostat would close and heat would build and reopen. After a cycle the temp would even out and it won't go below 180. If so, the temp sender could be faulty or the gage accuracy could be off.

Or, like me, you need glasses. :lol:
[addsig]