Thread: TD5 dont trust the temp gauge

Pretty much. Graeme on here did a heap of research into this.

Unless the engine is cold the needle comes up to normal and it stays there until it has basically overheated. As soon as that needle budges from normal you've got to stop - as in as soon as it moves, and I think one of the findings was also that it may even move into the hot region when things are too late depending on how the calibration falls out. 107 isn't a problem though and the colder the ambient is the warmer the engine will run itself to compensation for temperature loss through the block. The other funny thing is that at 1500rpm and down the coolant flows an incomplete circuit and the motor will run warmer also. 107 isnt an issue though and wont hurt the motor, the fans dont come on until 110.

I suspect that a lot of people that are getting these diagnostic thingys are doing a lot of sweating over nothing, which is exactly the reason why LR have designed the gauges as they have... so there is no worrying over things that are perceived as a problem but are not.

107 isnt over heating for a td5, once you get to the point where you are out of the normal operating range for the engine then the temp gauge will start to move and do so obviously. (I think from memory actual overheating isnt happening untill you clear 120+deg C in the cooling system which is another reason to use OAT, wider operating temperature tolerances)

I dont think its such a bad idea unless something is wrong with your setup it will let you know when your startin to go over operating temp.


what would you rather have a temp gauge that moves up and down so much that you dont know what the max operating temperature is untill youve swung it up so high youve stuffed it

or one that pointed the needle vertically so that when something was starting to go wrong it would swing quite obviously away from its designated position.

Old school racing drivers and truckies used to swing their gauges around in the dash so that when everything was up to nominal operating temps all the needles were vertical anything left of center was ok or warming up and any thing right of center was bad or cooking. the usual exception was the oil pressure gauge and that came down to personal choice you could have it left was low and bad or left was high and not so bad and right was low pressure territory.

Thats right. Also Stack made a tachometer that moved very little in the lower revs and moved heaps when closer to redline.

Originally Posted by Blknight.aus

107 isnt over heating for a td5, once you get to the point where you are out of the normal operating range for the engine then the temp gauge will start to move and do so obviously. (I think from memory actual overheating isnt happening untill you clear 120+deg C in the cooling system which is another reason to use OAT, wider operating temperature tolerances)

I dont think its such a bad idea unless something is wrong with your setup it will let you know when your startin to go over operating temp.


what would you rather have a temp gauge that moves up and down so much that you dont know what the max operating temperature is untill youve swung it up so high youve stuffed it

or one that pointed the needle vertically so that when something was starting to go wrong it would swing quite obviously away from its designated position.

Old school racing drivers and truckies used to swing their gauges around in the dash so that when everything was up to nominal operating temps all the needles were vertical anything left of center was ok or warming up and any thing right of center was bad or cooking. the usual exception was the oil pressure gauge and that came down to personal choice you could have it left was low and bad or left was high and not so bad and right was low pressure territory.

VDO made an oil pressure guage that went backward so that and all the other guages, Water temp, Oil Temp, air pressure, boost, etc etc were all available so that the normal ranges were pointing straight up and if something was out of the ordinary then you could special order it.

I prefer to see whats going on but I can see why they have done it like that.

if the temp guage doesnt move when you are starting to have a problem,only reacts after it is too late & the engine is ruined....then it isn't worth having.

the tempguage on a vn commodore goes up& down as the electric radiator fan cycles....brilliant.you could easily see if a problem was starting to occur

i wonder if this "computer correcting" has caused many of the head gasket failures to occur as the temp guage did not react & alert the driver?

i have noticed with my td5,whether you are on the road with an ambient at 0'c or working hard in soft sand in ambient of 40'c,the tempguage stays in the same spot,so it is obviously"computer corrected"

maybe i need an engine saver, but it may only signal if coolant level is low.

Thats the thing I think that its setup so that so long as your under 3/4 of the gauge swing on the temp gauge then the engine is still doing OK.

Granted it might only take 1-2 minutes hell even only 15 seconds to go from the routine 1/2 to the "your about to pretzle your head" 3/4 mark but even if it did move how many people have you seen stuck on the side of the road with well and truely toasted donks that havent paid attention to the guages for say 20 minutes or so?

At least its still better than some vehicles that just have a check engine master idiot light and 30 or 40 other lights to tell you which door is open and which nuftie hasnt put his belt on.

Although I'll admit I have missed using the temp gauge to help gauge how hard Im working the donk.

Originally Posted by Blknight.aus

Thats the thing I think that its setup so that so long as your under 3/4 of the gauge swing on the temp gauge then the engine is still doing OK.

Granted it might only take 1-2 minutes hell even only 15 seconds to go from the routine 1/2 to the "your about to pretzle your head" 3/4 mark but even if it did move how many people have you seen stuck on the side of the road with well and truely toasted donks that havent paid attention to the guages for say 20 minutes or so?

At least its still better than some vehicles that just have a check engine master idiot light and 30 or 40 other lights to tell you which door is open and which nuftie hasnt put his belt on.

Although I'll admit I have missed using the temp gauge to help gauge how hard Im working the donk.

correct....a lot of people dont pay attention to the guages,at all.....but if they dont work properly...... then whats the point

if,for instance you have a slow coolant leak,say over a few weeks and the engine overheats slightly it would be good to know.a float in the expansion tank would also indicate this....i think the d3 has one of these.





i find the door open idiot light is good particulary if you have kids.on the disco the only way to tell if a door is not shut correctly is if the interior light does not go off....this is a nuisance as it has a time delay

as for working the donk hard.....yes it would be good if the guage did move.

we often have to turn the air off,or slow down at times in our work vans to get the temp guage to drop down below 3/4 when driving fully loaded with trailer on in hot weather.

A door open idiot light is good in a mates 5 door theres 6 1 to tell you that a door is open and then 5 more to identify which one it is.. FFS its even got a light to tell you the bonnet is open. IMHO thats just getting rediculous