Land Rover 109 gets a VDO temp gauge

OK,  With the stock temp sensor and gauge you can only tell relative temps. The gauge only has cold, normal, hot areas. When driving at 65 the needle would be in the red. If I drove at 58 it was just below the red. So how hot is that?

    I bought a VDO kit #310-1052 from www.egauges.com   It was supposed to have the metric adapters to fit, but Rover in it's infinite wisdom decided to use a nonstandard thread for the stock Discovery temp sensor. They used M16 x 1, instead of the more common M16 x 1.5.

   The VDO sensor is 1/8"NPT. There is no  M16 x 1 x 1/8" adapter. Anywhere.

Here's the stock sensor, #PRC8001 (orange);

and the VDO sensor and adapter

    I have been running the VDO gauge with the stock sensor and don't really know what temp things are really at. Then I bought a IR gun. I could now correlate the needle with temps and so I was able to drive to Panamint Valley and keep an eye on the temp.

Here's the 2 sensors side by side the VDO is smaller

I was able to find a brass reducer at the hardware store, while having a 1/8 NPT female it had a 1/2 male outside.
My thought was to turn down the outer portion and re-thread it for M16 x 1. I had already bought a die in that size.

A pic of the stock sensor, 1/2 adapter the M16 x 1.5 adapter and the VDO sensor

I asked my friend Brett to turn down the adapter and re-thread it;

In short order the work was done, Below is the VDO sensor on top and the new reducer in the middle and the old sensor on the bottom. The threads are the same length as the stock sensor 10mm. In the lower pic you can see the VDO sensor installed in the reducer.

    So once home I set about installing the new set up. Only 1 hiccup the new reducer takes a 7/8" wrench and there is not room for a socket to fit on it. I had to use the 7/8" wrenches I modified for the oil drain fitting on the underside of the turbo.

Once installed I refilled the coolant and hooked up the wire.

Next I started it up and checked for leaks, WOW! there wasn't one.......  Then it was on to seeing if the sensor moved the needle on the gauge. After a few moments the needle started to rise and I checked it with the IR gun...close enough!

I am looking forward to driving it and knowing where the temp is not just some vague, hot/cold.