Fresh sca coolant. Fairly new radiator. New radiator cap. New heater hoses and radiator hoses. Truck is over heating. Both heater hoses going to and from heater core are hottt. Top of radiator Is hot and the bottom is fairly warm. Yes I have aftermarket temp gauge as well. I tried the newspaper test for the clutch fan I'm able to stop it with some force from the newspaper. So I'm not exactly sure if the clutch fan is bad or not. Truck over heats now at idle. Was running fine few months ago.

 

It's not a fan clutch problem. It's likely your t-stat.


To test your fan clutch, spin it. If it spins freely, it's bad. If it spins with resistance, then it's probably ok.

 

Yup.

Unless the engine gets really hot(240F IIRC), the fan clutch won't lock up.
Which should never happen except when towing up a big hill in the middle of summer(at lower speeds really).

Thermostats are cheap and fail occasionally. Make sure to get a genuine Motorcraft thermostat - other ones tend to break very very quickly.
And the motorcraft ones aren't expensive either.

 

Again while running the fan is kinda hard to stop from spinning. But with some force I can stop it from spinning. Now my wife did let the truck climb almost to 240 while I wasn't home. A t Stat is cheaper than a clutch fan I just don't want to throw parts at it. And it over heats without a load. Just idle or normal driving.

 

Just because the hoses are hot does not mean the water is moving. With the caption off can you see coolant moving

 

No I don't. Thought with the cap off it won't pressurize so water wouldn't flow? Or am I wrong.

​​​​​​​I also figured since the radiator was hot up top and warm on the bottom it was circulating property which lead me to think clutch fan. But since yall say t Stat and it's a cheap fix I'll do it. Even tho its kinda a pain to get to it seems.

 

If you move the fuel filter and alternator it not bad. The water pump moves the coolant. Pressure is built by the heat. That why the caption is pressure release

 

fan clutch is really not needed, i removed my fan one winter because the clutch failed and the fan was wobbling. and forgot to put it back on once summer came. i ran it for 3 years with no fan

 

​​​​​​​really lol. I'll replace my t stat and post updates thanks yall

 

Indeed idle overheat is not fan related. These engines tend to stay cool at idle and low RPM. My fan locks up around 220*-230* and quickly drops the temp back to about 200*-210* before unlocking. This mostly happens when towing up a grade, and both the noise and loss of power when it locks up is very noticeable.

Last weekend after towing on the highway temp dropped to 150* when I got off into stop and go and stayed around 150*-160*. Coolant level was fine, aftermarket and factory gauge readings correlated. Back to 200* on the highway later. Normally it won't go under about 180* unless idling in cooler weather, I think my thermostat is on the way out or got some junk hanging it open. Sounds like yours may have failed closed rather than open.

 

Mine used to stay at 185 all day. I was just thinking fan. But a t stat Is a cheaper fix.

 

i agree, it sounds like your t-stat is partially suck closed.

 

They will fail /closed/ due to the design of the t-stat - there's two metal tabs holding the whole thing together. If one of them breaks(and they are the weakest point), the T-stat will stay at least mostly shut.

A stuck-open t-stat more than likely got a piece of crud in it, especially if it happened temporarily

---------

While you are replacing the T-stat, you'll have the upper radiator hose/top-half of t-stat housing piece on your hand.
You'll want to remove the old cruddy gasket, and when you do, you'll see a small hole with a little ball bearing ratting around in it.
This ball bearing is a check valve that is supposed to allow air to bleed past the t-stat.

I always just /remove/ the ball bearing. This allows a small(1/8" or so) passage past the t-stat to be open at all times, but it doesn't seem to affect warm up time at all.

The main affect is that it makes bleeding *much* easier, as the air will just come up that passage and not get stuck around the ball bearing, which seems to happen a lot.

It means that a refill will take all of the fluid at once, and not require a heat cycle or 3 to fully purge all of the air out.

 

You don't have oil in your coolant do you? When mine did this, new, it was an oil cooler failure. But you could see the oil in the coolant. Just a thought.

 

what temp t s due idi use,?