mellowgold

BTW Kal... no wax in that unit... it is apparently some sort of layered sandwich of unusual sounding metals that undergo some sort of change in shape or properties at different temps... read about some guy who took his apart with the idea of cleaning it and found there was no sight of wax... and on investigating he said that at some stage in the past, wax was used in such devices

Old thread, but Kaldek's videos have been very helpful for me. Kaldek, I owe you a beer or three. Here's a photo of the internals for reference...I took mine apart (sixth gen) last night to see if it needed servicing, but I honestly can't see how this unit would ever fail. It's just a spring and some metal bits. Mine looked brand new inside.

Now, that said, the coolant passage was almost completely plugged on mine and wasn't allowing the unit to heat up properly:

Before:

Now to go buy some circlip pliers so I can get the bloody thing back together...