the blue tooth setup's are pretty cheap and the app is free. when i use my lazer pointer temp gun, i get all sorts of temps on different places on the cooling hoses, and the reservoir seems to be the hottest point. lower hose seems to sit around 80's to 90's while the rest of the hoses are around 150.

 

The dash gauge doesn't have to go all the way to the red for the engine to overheat. I have used several different different aftermarket gauges and it is highly necessary. I forgot to tighten a hose clamp one time and when I checked the gauge my coolant temp was 225 and climbing whilst the dash cluster gauge sat happily at normal. I know for a fact that that it doesn't start moving from the normal position until the coolant gets up to about 240-250 degrees so you are a fool for continuing on referencing it when there are hundreds of threads on the subject and just about everybody's signature has something about an aftermarket gauge included in the list of mods. You probably already damaged the engine block. Keeping temps low is essential and no need to disregard. Aftermarket devices are cheap and abundant. If this car is for a kid, all the more reason to install a gauge with reliable sender and audible alarm set on your own preference. People have reported real damage with these rover blocks at temps well under what you are experiencing on a regular basis while experimenting with your cooling system. Take this as a warning. One day you are going to have a brand new ticking noise or worse.

 

IR therm pointer on intake manifold/temp sensor gets very close to my ScanGauge reading.
......

 

Yep the temp gauges on most modern cars is no more than a joke these days. If you want real-time temp readings grab an ultra-gauge, Scangauge II, OBDII Bluetooth Device, or hook up actual gauges.

If the gauge moves above half of you activate the red warning light on a LR = that motor is more than likely toast.

 

I appreciate everyone's help. I did point the IR reader at the intake manifold and the area where the temp sensor is behind the AC pump. It did not get any higher than 150 to 160 near the sensor and a lot lower on the intake after 10 mins of running. While performing all of this work I did install a new temp sensor. Maybe it is faulty? I am going to go ahead and get a OBD11 monitor so I have an audible warning. I will let you know how it goes.
All the best John.
All the best John.

 

Using the handheld IR reader I'm not getting anywhere near the 200 or so you mentioned. Where the temp sensor is behind ac pump its around 150 to 160. I'm going to get an after market monitor with audible warning to be on the safe side. I am aware the dash gauge is unreliable but have never experienced this erratic behavior before in the 11 years of owning this truck. I'm thinking the gauge itself is faulty or I have a bad sensor?
Thanks John.

 

I just installed an ultra gauge. After about 10 minutes of running it starts to climb. I shut down when it reaches no more than 221f. After this much time I can feel that the lower hose to the stat is still cold? Could this be another bad stat? This is the third one. Also the radiator is still quite cool. Engine seems to be running smooth and quite.
Any more suggestions would be great.
Happy Christmas John.

 

That is exactly why it is suggested to just step up and buy the OEM 180 degree stat from the vendor of your choice. Aftermarket stats are notoriously bad and you do not want to go there with these engines.

Originally these trucks were designed to run at that temp, for emissions reasons. It has been later found to be better for engine life to run the OEM 180 stat factory spec'd for the TD5 engine.

It costs more but you only buy it once.

Lucky 8 usually has a good deal on it.

Satisfied customer.

 

are you starting up and just letting it idle up to temp? or did you drive it down the road to temp?

i noticed when i was trying to bleed my system i would get fast climbing temps with just and idle up. i revved the motor to 2000 rpms and it finally started making heat in the vents and the thermostat seem to be passing coolant threw and heating up the lower hose and radiator started drawing heat out of it threw the fan.

 

Thanks Dave.
I went to lucky 8 and there seems to be a few there. Is there a specific one you are talking about? I'm guessing you are talking about the low temp grey one? So from my understanding I definitely have a bad stat situation when the lower hose is still cold?
Appreciate your help. I miss the truck and the weather is getting bad. My old 68 Mercedes doesn't cut it in the snow
Cheers John.