Temperature Gauge Sender combination Woes

I'm sure this is covered accurately somewhere but there is soooo much conflicting waffle on the net around this i thought it best to ask.

I have a Defender 200tdi with the gauge PRC7311 in it. The temp is reading at the top of the white are just before it goes into the red. However, the engine does seem hot and i have put one of those laser thermometers on it and its fine.

I'm guessing the PRC7311 is from an earlier defender and i have the correct 200tdi sender in the engine giving this false reading.

Does anyone know with any certainty what sender should go into the 11L 200tdi or am i best to change the gauge to a later one to match the 200tdi sender. Or is the gauge i have correct and have a fault elsewhere?

Thanks in advance

Just a word of caution, I have a 200 tdi Defender with the original gauge in it.( don't know what a PRC7311 gauge is) I did have a problem with the sender unit a few years back. I tried Brit Part and went through three gauges in less than three years. I then bought one from Bearmach which has now been in three for about four years. Just thought I would mention the above.

I have pretty much the same reading after retro fitting a Disco 200tdi into a 1985 90". The infra red thermometer says all is OK. The needle rises to just below the red, then the thermostat opens and it drops back to 3/4. I guess the later gauge should read lower, but I've bought a Durite gauge that actually tells you the temperature to remove any doubt. Before you spend any more on getting the LR gauge to read correctly, might be worth thinking about. Around £40 for the gauge delivered and you'll need an adapter to fit the durite sensor to your head, which costs a few pounds.

mikescuba said:

Just a word of caution, I have a 200 tdi Defender with the original gauge in it.( don't know what a PRC7311 gauge is) I did have a problem with the sender unit a few years back. I tried Brit Part and went through three gauges in less than three years. I then bought one from Bearmach which has now been in three for about four years. Just thought I would mention the above.

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Yeah cheers, i don't want to chuck good money after bad!

zeaphod said:

I have pretty much the same reading after retro fitting a Disco 200tdi into a 1985 90". The infra red thermometer says all is OK. The needle rises to just below the red, then the thermostat opens and it drops back to 3/4. I guess the later gauge should read lower, but I've bought a Durite gauge that actually tells you the temperature to remove any doubt. Before you spend any more on getting the LR gauge to read correctly, might be worth thinking about. Around £40 for the gauge delivered and you'll need an adapter to fit the durite sensor to your head, which costs a few pounds.

Click to expand...

Any idea what the thread is on the defender so i know what adapter/sender to get?

Have a look at my recent thread on this. The thread is either 5/8unf or m16x1. The second adapter is not widely available.