The 25a does not ring a bell to me right away. The part I am thinking of is "Impco Model Jb-2 Propane Convertor Regulator". Also if this unit has a flow restrictor in the coolant hose I would remove it and just install a standard fitting. I have had quite a few of these plug up as the units get older. In any case I will do my best to get you all the info you need.
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