For those scratching there head looking for a place to put the sender,this might interest you

On after market Koyo style rads there is a bleed bolt which is 12mm x 1.25P and depending on your gauge the sender is 10mm x 1.00P for the celcius or 1/8 NPT for the Fahrenheit... I have a lathe so i drilled the 12mm bolt down the middle and tapped a 10mm thread in the centre to take the sender,then run the tool across the head to reduce its height...After this i turned the bolt down to reduce its lenght so that the tip of the sender was below the bottom of reducer. PTF tape around both the sender and reducer and screwed them into the rad and checked for leaks..All good and no need to buy a hose adapter and start cutting the top hose up too plus it cost me half an hour of my time thats it:yes:

nice place ... but does it hit the bonnet ..

 

all so does that adapter fit in the drain bolt hole at the bottom ?

Id be wary of that not being in the water though and giving false readings, ill stick with the top pipe location as its slightly lower than the top of the rad.

that was my other thought too

I'm with Voddy on this too, theres always an air gap at the top of the rad so there will be a margin of error, best place is to tap and die a new hole on the top waterpipe.

funny enough guys i thought the same about air gap BUT after running temp has come up the air gap goes (thats the idea of bleeding)...try slowly taking your caps off,its right up to the top of neck. To answer Marks question about bottom rad fitting,thats out the window as the temp down there is cooler and not a true engine temp reading. Anyway to answer the sceptics (i was too at 1st) the reading right up the scale on the gauge is the same as conzult so it seems fine;)