Cant Figure Out Overheating

[dudefromflorida]

Latley my Ex has not liked to idle. I can run it all day in the heat at highway speeds and around town with no problem. When I idle and sometimes in traffic it tires to overheat. Sometimes at idle it will take 2 min to overheat, others it will not overheat for 10 min if at all. I have replaced the thermostat, flushed the system, and new radiator cap. Yet still it overheats. Any other ideas or anything I am missing? Could it be the fan clutch? Im lost.

 

[mr cribb]

Quite possibly the fan clutch. I believe another member had or was having similar issues and it was mentioned in town overheating was most likely linked to the fan clutch.

I'd also check your fan blades, as most 1st gens are cracked. If you were going to replace the fan clutch might as well replace the fan blades as well since the two items are attached, unless you have recently put a new fan on it.

 

[mr cribb]

I see your town listing in NC.... I traveled through there on my way to Raleigh several times. I just left Bragg a few months ago.

 

[Delta_1980]

your radiator cap could have failed and wont hold the pressure in the system while your moving slowly around town. no visible leaks but venting pressure and lowering boiling point. its worth a try.

 

[Patened]

i was having the same problem.

I have a 1991 ford explorer and i ran into the same problem, i replaced the t stat 3 times flushed did a bunch of ****. So i decided to put a fan shoud back on the explorer and it never over heats now even when 4x4ing in heat, it does boil sometimes when im stuck in the mud and gunning it, lol i would recomend that you make sure the hole is at noon and go and get the truck up to operating temp and drive onto a steap hill and pop the raditor cap that way the rad it higher then the engine and it should burp the sysyem. Another thing to do it invest in a flex a lite and drop the clutch and get the flex instead and you will prob never run into over heating.

 

[dudefromflorida]

I have replaced the T-stat, temp sensor, the radiator cap is new (first thing that i replaced), and flushed the system then properly filled and burped it. It still overheats. The only things left are the fan and the radiator. My only thoughts about the rad is if it were that it would overheat all the time, (and thats not the case, also please correct me on that if I am wrong). So for lower rpm problems I can only think of the fan. I want to wear out all other possibilites before I tackle the fan, because if I tear off the fan cluth I am going to be too tempted to go with an E fan. I know that this is a very far guess but is there any way possible that my guage inside the truck is not reading right since the overheating is random? Also if that is the case what is a way to check to see if it is accurate?

 

[jd4242]

You buy a cheap mechanical gauge and put it in

 

[jd4242]

You can test the fans clutch just to give you an idea if its bad by letting it get up to temp or overheating point.shut the truckboff and see how hard it is to spin by hand,with the truck off!it should be tight or hard.no oil in the water or water in the out?

 

[dudefromflorida]

No mixture of fluids. Oil is fine, and water is fine. Also there is no loss of coolant. I will check the fan clutch out and see how hard it is to spin after driving to work this morning.

 

[s10 warrior]

sounds like a bad radiator. my old one did the same thing.. while driving it was fine, the air rushing on the radiator kept cool, sitting in traffic itd start to overheat, once moving again ,the temp would drop..

 

[mr cribb]

How well does the heater work? Possible heater core issue, that's what my issue was when I first got it. That was $23 and 20 min of work, no more overheating issues.

I don't think it'd be the radiator if you're not losing coolant. Are the fins on the radiator straight and not all jacked up?

 

[toomanyfords]

fan clutch

If it were my truck I would put a fan clutch on it. Seems obvious, has to be either that or the radiator. try taking a garden hose when the truck is cool and spraying water through the radiator fins, watch the other side for a spot where water does not go through, will show if theres an obstruction in the radiator fins. other than that sounds like a fan clutch

 

[dudefromflorida]

I believe your right toomanyfords. Sorry it has taken a while to respond, I have been gathering information to post on here about the situation. I have recently put in an aftermarket thermostat to better comfort myself knowing the numerical temp insted of N-O-R-M-A-L, I have learned that when first started I can let it idle alllllllllll day long and it will never go above 195. When I start to drive let the engine really work then idle again there is no cooling it down unless I turn the heat on (yes my heat works fine mr cribb). I will try the water trick tomorrow to see what the rad looks like. But i am really thinking that it might be the fan clutch and if so I am going to do an E-fan swap. The reason for leaning towards a problem with the fan is how it can stay cool fine until it really has to work to bring the temp back down. I would think it would always have a problem if it were the rad. Also how much harder should the fan be to spin from the time I check it on a cold start to after I drive it and check it at an engine temp of 210ish? WHen i checked after driving it, I could not really tell a very big change if really there was one at all.

Thank you again everyone for your input and hopefully afer the water check and whatever answer I get about the resistance difference this problem will be kicked to the curb.

 

[intelisevil]

My bro-in-law's 91 had overheating problems similar to yours, he replaced everything except the radiator.

One day he was looking at the front end and noticed the A/C condenser was plugged with dirt and bugs. After he cleaned that out he's back to normal cooling.

 

[s10 warrior]

I don't think it'd be the radiator if you're not losing coolant. Are the fins on the radiator straight and not all jacked up?

just cuz it dont leak dont mean its good. my last explorer i had,when you touch the fins on the radiator, they would flake off. must have been the salt air?

 

[dudefromflorida]

Wow. Completely forgot to give the final answer. It was the fan clutch. Thank you everyone for your input and help. Glad that it is finally running well and CONSTANT!!

 

[mordred612]

Help!

I did a job on my car last weekend and replaced the blend door actuator by following the steps in one the the posts here. It worked fine for a few hours then when I was turning it down to a little cooler temp I lost it all the way. I travel all the time and my car sits for a week or two at a time. This week when I came home I started it up and no heat as I left it. While I was driving home the check gauge light came on and and pulled over because the temp was high. What was strange was that it was hot then back to normal then hot again. I replaced the temp sensor and thermostat already. The upper hose is hot and feels like it has pressure in it. The hoses going to what I believe is the heater core on the firewall aren't hot. I'm at a loss and need to get it fixed.

I do have a slow leak, but there is coolant in the overflow.
The upper hose is hot and feels like it has pressure in it.
The hoses going to and from the heater core are cold and I have no heat.


I'm at a loss.

 

[Roadrunner777]

If this is on your 2003, you should repost in that section, this is for 1991 through 94. That said, if this were a '94, I would check the heater diverter valve. I don't know if a 2003 even has one.

 

[mordred612]

Kind of chaps my butt that you can't just open the radiator cap and take a look at the fluid and see what level it is at or see if it is flowing through. I really miss my Jeeps.

 

[Currency]

My radiator leaks at the very top, if I keep mine from getting completely full it will not leak. An old friend suggested a lower pressure radiator cap which reduced the leakage and this could help pressure in your system.

Since you flushed it, replaced the cap (what pressure is the cap?), and replaced the T-stat, I would look for leakage around the heads or intake. If it is not leaking the problem is elsewhere. Like others stated, check the fan. Mine has cracks in it but works fine. The only time my explorer gets hot, half on temp gauge, is when I run it extremely hard.

Not sure about the T-Stat in mine, but someone replaced the intake gasket at one time before I got it about two years ago. No over heating though.