Relic of main alcohol valve with manufacturer code aeq (aeq = Bartoc & Co., Maschinenfabrik u. Giesserei Hedwikow,bei Caslau (Caslav) Czech Republic). An air (nitrogen) inlet pressure of 440 to 530 psi (30 to 36 Bar) was required to close this valve against its internal spring and the force of the turbo-pump. The large nut at the top is the connection for the fuel return (or 'revolving'line) pipe, and the air and electrical input ports can be seen to the right (air), and left (elec.) just below this point. V2RH image
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