hey everyone i though i had figure out the overheat problem but this morning i was driving to the job site and the temp gauge was below middle when in 5 mins of driving so here is what i have done so far to fix this problem ....

put in a T Stat 192deg since SPOT took it out lol
replace one coolant temp sensor ... order the small one
change out anti freezer when i brought it since it look like water in system
adding 1 bottle of WaterWetter

also check the clutch fan and it feel and look good

 

Blocked rad?
Do you have a "real time" OBDII scanner? the OT2 is great but $200 or so and needs an iPad-iPhone i-Touch to run the app. The ELM ??? (can't remember the number) is cheap but needs a laptop.
The dash temp gauge stays steady in the middle untill the engine coolant temp. goes over 110 celsius, then it shoots up under the red so you cant use it to tell the engine temp.
You say that the viscous unit "feels" good...
I had two fail on me!
I now run electric fans. The unit from a ford contour (and usen in many other fords) has 2 fans and is wired for both low and high. Since the fans are smaller, there is less rotational mass and the regular 30Amp relay is enough (the Crown Vic. one draws 52Amps at start-up!!!)
If you try the electrics, the Contour just needs 2 slits cut at the bottom to fit where the Disco cowl sits and 2 holes on the top fot the Disco clips.
Use 2 standard relays and a SPDT switch (it has 3 connectors: the center either connects to one side, is off or connects to the other side.) A DPDT works too. An automatic controller like the SPAL can be $200 or built for $20 but you need to know electronic.
With temporary electrics you can rule out the fan clutch.

SD

 

Check out "$27.99 - ELM327 USB Vehicle OBD-2 Scanner Tool - OBD-OBD2 Car Diag. Tools" at
$27.99 - ELM327 USB Vehicle OBD-2 Scanner Tool - OBD/OBD2 Car Diag. Tools

The problem is the software, but there are other free softwares that work with it.
Also look up laptop recyclers for deals on used laptops. Mine just cost me $45. I just use it for the car and it has the RAVE and if I brake it... it was cheap.

SD

 

For the age of your truck, I would advise you get your radiator cleaned out, check your viscus clutch and make sure both electric fans are working, Might also go back to a 180 t/stat.

 

In the summer with the a/c on the engine is going to warm up quick.
Did the truck actually overheat?
Or do you just see the faster warm up time as a pending problem?

 

AB has a special on a ODB II with live data capability ofr 99 bucks, got the circular this morning in the mail. Sounds like it might be a good deal.

 

if i drive to the job site and shut it off when i get in it and crank it up.. the needle is right below the middle line but once it was boiling at expansion tank and antifreezer going on the ground and temp gauge was below middle when that happen... also i check the engine block and i cant bare touch it.... do you think if i rent a scanner from auto zone chould it check temps.....if you curious about oil light issue i change out the sensor so far no light

 

The oil light is coming on>? Did you check the oil level?

That is usually independent of temp issue.

 

no a old problem after i brought it and i forgot to post on it topic

 

Sounds like you have air in the system.
If the temp sensor is not immersed in coolant it will give a false reading.

As for the scanner from AutoZone, you need to make sure it reads "live" data.