oooooh ok, maybe time for a replacement then.

What an (expensive) thing of beauty
 

neil wrote:

Test it Mark : )
 

Sure does work, and opens much better than the old one!
 

ohh shiny!

they dont call em yellow money boxes for nothing. when we bought the new rad cap for the d4 mum was not impressed with a invoice for $150 thankfully it appears our thermostat works just fine where we are it doesnt really get cold enough to need one.

Just a quick update on progress.

Here is the new thermostat all in place:
 

And the puller I made to remove the brass ring, which combined with the steel plate with holes in it worked a dream:
   

I've since completely rebuilt the water pump with new bearings (6305), SKF CR13651 seals, and the genuine 4N7526 carbon water seal and reinstalled it:
 

Next is to put the radiator back together with new gaskets top and bottom to see if I have stopped the slow coolant seep from the top LH corner.
 

Kurt wrote:

Nice work - thanks for the photos

Thanks Kurt, and I appreciate the sacrifices you have made to take up the role as President - I can't say that the road ahead will be easy, but you have my support.

On another note, it's the threads in this forum that have lots of pictures and detail as to part numbers that I find the most interesting, informative and helpful - so I try and put that experience in to practice!

When I stripped the tractor down I found a persistant leak of coolant from the top of the tubes of the orginal Milwaukee made Perfex core. The core was in beautiful condition otherwise, but the solder had started 'blooming' (corroding and turning to powder) both at the top and bottom where the tubes go through the brass plates. A replacement core is over $2000USD so I took it to my local radiator shop (who has a great reputation) and they have done a great job of re-running the solder. It remains to see if it leaks, but my hopes are high!
   
And all soldered up: