Thread: Defender 200tdi Overheating Issue

I used an IR temp gun to watch over the temps.

Mine started to open in the high 80's.
Was hard to control an exact temp, and being the impatient type I did have the heat gun at the highest setting.

And to be sure, I did test it in this manner off the car.

Originally Posted by chip.daniels

Hi all, I have a 1992 Defender 110 with a 200tdi which over the past 12 months has slowly increased it's 'operating temperature', to the point now where the needle is just below the black blank area below red hot.

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Also:

I had similar issues with my old '79 RRC many years ago.
I was out on a 3 day drive and on the 2nd day the RRC did exactly the same thing. At the time I had twin electric fans on the car, removed the VC fan. Temp gauge showing at the red line suddenly. No problem on the first day, just started the next morning ... 'out of the blue'.
I checked temps by hand, there was basically no pressure in the hoses, could put hand of them for a few sec, i.e. not massively hot, but more importantly it didn't actually feel like it was at the temp that the gauge was indicating.

I changed all manner of stuff, even removing electric fans and replacing VC fan too, tempo sender, etc. Not being able to work it out, it ran like this for a couple of years, as I just couldn't figure out what was wrong ... even though nothing actually felt wrong.
One day I was working on (I think) harmonic balancer, to do the front seal .. and I rubbed against the radiator and it crumbled into dust.

pulled rad, turned out it was just old and rotten, replaced and bingo .. temp gauge back to normal.
For the two years it ran at the redline, it never once felt it actually ran hot, never ran with high pressure on coolant hoses, and just 'felt' normal.
RRC of this era had an oil temp gauge, and this never showed excessive heat in the oil either, always ran in the low zone. One time, just to confirm this I ran the car at higher speed for a few minutes and oil temp did rise to about the middle range on the gauge.