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If the LO (local osc.) is not running, try reversing the connections of either the primary or secondary (but not both).
FWIW, it's not "the IF" which needs to oscillate, but the LO. Think of the first two grids in the tube as a triode, with the second grid acting as 'plate'. The LO tracks 470 khz higher than the received signal. The two signals mix to generate the 470 khz IF signal.
Say your station is at 600 khz; the LO will be at 1070 khz, and so on up the dial. In fact you can use a second radio to hear the LO of the problem radio, to tell if it's tracking correctly.
Did you check that 40K resistor carrying B+ to those screen grids?
Last edited by old_coot88; 10-11-2016 at 09:06 PM.
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