I have been off here for a few weeks and now I am needing assistance. My engine was overheating almost the whole way to CO from KS and all the way back. It ran in the high end of the "normal" range a few times.
Most guys say that you can hear the fan kick on and say its really noticeable and loud. I either dont hear it or mine doesnt do that.
How do I check to see if my fan is operating or not?
Thanks
Thad

 

Normally when I encounter that problem I'll replace the thermostat first, just because it's so much less expensive than the fan clutch....but it does sound like the clutch isn't locking up.

 

With your motor off turn your fan if it turns pretty free or you can spin it the clutch is bad, it should have quite a bit of resistance. If this makes any sence to you this is kinda a crude way to tell you but the only way I know.
The fan will not lock up until around 205 I'm thinking you may not be getting hot enough to lock it up have you lost any water.

 

well,
There is some resistance but not much. I am thinking that could be part of my issue.

Water is full up to the top. So, if anything my issue is probably fan related. I may try to replace it, after I put the new thermostat in.....

thanks
Thad

 

If it is still in the normal and you haven't lost any water your motor is probably not hot, it should run around 200 degrees normally.

 

If you change the thermostat get one from ford or international aftermarket ones will not work.

 

To test the fan drive the truck untill it is good and hot then pull over and shut the engine off and try to turn the fan if you cant turn it it is good if you can its junk. I think mines junk as when i turn it off the fan keeps spinning round and round and there is litle ressitance but I havent checked at operating temp as my truck isn't running hot .

 

I have a test procedure that I looked for yesterday and did not find.
The way the weather looks outside I will look more today.

Blocking the radiator to get the heat up is the process you use.

 

the first thing i would do before i done anything else is buy a real water temp gauge install it in place of the factory one and go for a drive.

 

Here it is, kinda long.

Engine cooling fan clutch test

The purpose of this procedure is to determine whether the fan clutch is functioning properly, or to determine if the clutch is not engaging, not disengaging, or causing vibration. Worn or damaged cooling fan clutches should be replaced with the proper service part. Do not attempt to modify the bi-metallic coil on the face of the fan clutch.
Locate a piece of cardboard large enough to cover the front of the radiator and an engine tachometer before proceeding with this diagnostic test.

1. Turn off air conditioner, heater - A/C fan, radio and any other accessories.

2. Before starting the engine, rotate the fan by hand. It should have some viscous drag, but it should turn smoothly during the full 360 degrees of rotation. The fan clutch should be replaced if it does not turn smoothly, or if it does not turn at all. If the fan clutch spins with no viscous drag when it is cold, and has not been run for an hour or more, it should be replaced.

3.To check for excessive fan clutch bearing clearance (cold fan clutch), hold the tip of the fan blade between the thumb and forefinger and lightly pull toward the radiator, then push toward the engine, repeating the motion several times. The total rocking movement at the end of the blade should be 5 mm (2/10") or less when no more than 8 ounces of force is applied. A force greater than eight ounces may deflect the blade and give erroneous results. Replace the fan clutch if more than 5 mm (2/10") of movement is observed.

4. Install a temporary engine tachometer if the vehicle is not equipped with a tachometer.

5. During the following tests, be sure to monitor the coolant temperature (temperature gauge in the instrument cluster) and shut off the engine if the temperature rises above the maximum recommended limit for the engine, or if coolant is discharged outside the system. The tests can be resumed using the following procedures after the coolant temp drops off to a normal operating level.

6. If the hood is left open, the fan noise may be easier to hear.

7. Start the engine. The fan clutch may be engaged when the engine is first started. This will be apparent from the noise level which has a distinctive roar. The fan clutch engagement is due to the viscous silicone fluid draining back and filling the gap between the input and output components. Running the engine at a consistent speed of about 2000 RPM should pump the fluid back to it's reservoir, disengaging the fan clutch after no more than five minutes. As the fan speed drops declines, the noise will drop off to a level inaudible to most observers. If the fan does not disengage after five minutes at 2000 RPM, the fan clutch should be replaced.

8. Stop the engine. Cut and install a piece of cardboard large enough to cover the front of the radiator with a 6" diameter hole in line with the fan clutch. If it is not possible to install the cardboard directly against the radiator, attach it to the A/C condenser.

9. Start the engine. With a gasoline engine at 2700 to 3000 RPM or a diesel at 2100 to 2300 RPM, the vehicle coolant temperature gauge will rise at a steadily as the engine warms, then appear to level off for a short time when the thermostat opens. Make a note of the temperature gauge position when the thermostat opens. The engine coolant temperature will continue to rise until the fan clutch engages.

10. Continue to observe the coolant temperature gauge. As the fan clutch engages the fan noise will continue to increase and then level off at full engagement. The fan may cycle off and on during the initial engagement. If the fan does not engage before the maximum safe operating temp is reached, it should be replaced.

11. After completion of the above tests, shut off the engine. Remove the cardboard cover from the front of the radiator. Restart and return the gas engine to 2700 to 3000 RPM or the diesel to 2100 to 2300 RPM, continuing to watch the coolant temperature which will begin to decrease. The fan RPM will drop to a reduced noise level where it was before the cycle began which indicates the fan clutch has disengaged. If the fan clutch remains engaged and the coolant temp has dropped below the thermostat opening temperature for at least five minutes, the fan clutch should be replaced.

12. If the fan clutch is replaced for any of the above test steps, the test should be repeated to verify the fix and owner satisfaction.

 

I drove without a fan alltogether for a few days without very many problems, then only time she would get warm is idling in town.

 

I dont get how this test would work with the fan dissengaged and the vehicle sitting still there will be almost no air flow threw the rad and air flow threw the rad is what heats the clutch to engage it. Just about every company that buys trucks that idle or run low speed such as airport fule trucks mistakenly buy trucks with viscuse clutches then bring them in for an overhaul while almost new if they are smart or the sales guy knows what they are doing they will get either an air clutch or a twospeed(viscus/air) so that the cluch can be engaged by the ECM if there is not enough air flow to heat the viscus clutch.

So is something diffrent about the older viscus clutches? or is there some other explination of how the test works?

 

The 6" hole in line with the fan clutch will let enough air through to heat the bi-metal strip.
Even with the clutch free wheeling the fan, it still turns enough to draw air across the bi-metal strip.

 

I wounder if they do something diffrent with the newer viscuse on the 466 because i've seen a lot of newer trucks that run lowspeed or idle alot need overhauls due to not having enough flow over the bimetal stip and overheating but it could also be due to the shape of the grill or rad or design of the blades on the newer one. Since i've seen plenty of low speed trucks with older 466s and T444Es that have viscuses and are fine.

 

I would guess the newer 466 is getting run at much lower RPM that a 444 ever was.

And I bet the newer 466 is getting run at lower RPM than the older ones were.

Grill design and aerodynamics is probably playing a bigger part than engine RPM though.
To easy for the air to spill around the grill instead of having to go through it and the radiator.