So went to go hit the trails last night and started over heating.....

[muddfildvaynes]

So i was going with about 5 buddies to hit the trail last night and noticed I was running a little hot when we got onto the trails.... The temp gauge was literally 90% up almost to the H; so I turned my engine off and popped the hood and let it cool down for a few because my radiator was boiling; after it cooled down I checked all the fluids and they were ok, started it back up and went maybe a mile and it shot right back up, turned the heat full blast and it cooled down a little to half way. Decided to call it a night and left to go home and ran my heater full blast the whole way home and if I was going above 40 mph it stayed cool but when i stopped at a red light it got hot again.... So i am thinking its my thermostat.... Its $25 with a new gasket so I am going to change it out and hope thats it. Any other ideas?

[Pezzy]

Your truck sees a lot of mud, take the rad out and clean it.

 

Mine was overheating all summer, and I had cleaned the rad a few times in the past, but the hose doesn't get really get in there... there was a truckload of muck in there!!

[silverton]

definitely clean the radiator, but if that doesn't help, your water pump or thermostat could be bad. With a non-spinning water pump the cold and hot water will still move through the system, one reason why it's necessary to have a proper radiator cap that keeps the system pressurized.

[skulptr]

how's your fan's performance? mine did that too, and then my fan clutch went out the following week.

[YoungWheelsCT]

check your belt perhaps it has snapped maybe?

[skulptr]

if a single one of his belts snapped, he'd know right away. if the a/c belt snapped, no problems, if the fan belt snapped, then no alternator and no water pump, and the dash board would be flashing like crazy to get his attention. broken belts are definetly not it, loose is possible, but he'd hear them squealing, or notice a dip in power from the alternator, triggering dash board lights again.

[muddfildvaynes]

Well my radiator is clean i checked it out, when i went to go put the thermostat in today the radiator was 25% filled.... where did my water go? Maybe the overflow is cracked? And I flush my radiator every so often because of the mud and abuse I put my truck through.... It is definitly not the belt and the fan clutch is perfect; I just replaced it when my a/c compressor went out because I noticed it wasn't working properly. Once I put water in, it started to run normal but a little hot but not as hot as before so I put a new thermostat in and its perfect now. My only question is where could my water have gone?

[XPLORx4]

When you overheated, the water boiled out the overflow tank.

Edited September 19, 2010 by XPLORx4

[skulptr]

 

if its boiling out that much, your antifreeze/water dilution is too much water, not enough antifreeze.

[Kingman]

Too little antifreeze in the system will not cause overheating. It'll help a little if the engine starts to overheat, a proper 50/50 mix has only a 13F higher boiling point than straight water. The pressure in the cooling system, 15PSI, is what is supposed to keep the liquids from boiling. Did you look at what was coming out of your tailpipe at all? Maybe take the over flow tank out, and fill it with water to see if that's leaking. Another thing you can do is get a cooling system tester. All it is, is a radiator cap, rubber tubing, and a squeeze pump with a gauge on it. You can pressurize the system to 15PSI and see if any hoses start to leak.

[XPLORx4]

You might also check the radiator cap. If its spring is too weak, it won't allow the system to pressurize.

[muddfildvaynes]

Thanks for the tip, I was going to pressure test the system this week and see what it does... The good thing is I have another DD that I can drive around while I am trying to figure out whats happening with my pathy... Although I took it out yesterday and wheeled the sh*t out of it and it never went above halfway on the temp gauge...

[Northernpathy]

The exterior of the radiator might look good, but you could be blocked up inside.

 

Friend with a 98 pathy had a lot of over-heating problems that came out of no-where. All of a sudden he would start over-heating and the fluid boiling out of the over-flow. He couldn't use the a/c anymore either, as it would cause the engine to over-heat within a minute or two!

 

Rad was clean on the outside and looking in through the cap it looked good too.

 

He flushed it out a few times with no difference.

 

We changed the rad 2 weeks ago and there was a huge difference. First of all it took a ton more fluid to fill it (like double the amount he used before to completely fill the system). Meaning that a lot of the rad tubes were likely blocked. Even after more than a few flushes it didn't help clean that out. The only option in that instance is a new rad.

 

Once changed the engine has always stayed nice and cool with no problems. We put the a/c on full blast and drove around for 15mins and it always stayed at normal operating temps.