Yep, big surprise when I bought the first one from NAPA. One
little seal about the size of a quarter.
http://www.pbase.com/dennygraham/image/113817419 Like Alvin posted, the biggest problems with rebuilding these
is the four tabs. As with any part that is not meant to be
disassembled, once the tabs are folded over you might get away
with unfolding them once, but not a second time.
Setting the tabs after you put the new seal in can be a
challenge. I made a special shaped driver and anvil to set
mine.
http://www.pbase.com/dennygraham/image/113817543Before you put to much effort into one, make sure the tube
and diaphragm are still sealed and haven't developed a leak.
Freezer and boiling water test worked for me to verify that
it was still tight and working properly.
And to answer your question, about what it does....simply
controls the flow of water. Adjusting the knob simply moves a
cam putting more or less spring pressure on the diaphragm.
Not the most sophisticated thermostat in the world and
really doesn't regulate the heat level all that well.
DG
