[R-390] R-390 Oldham Springs

[rbaldwin14]

Working on an R-390, I find that a prior owner seems to have omitted the tension spring on the Oldham coupler that connects the RF deck to the crystal oscillator chassis,  How important is this item to the performance of the receiver and what might be a good source of such a spring?  The appropriate spring is on the Oldham coupler on the PTO shaft.  Are they the same spring?

Also, on replacing the RF deck with the dial set to 2.000 Mhz, it seems that the Mhz tuning shaft cannot be set completely counter clockwise.  Is there a process for setting the Mhz shaft correctly?

Thanks for any guidance you might be able to offer.

Rich Baldwin
KD6VK
Durham, NC