1964 Zenith 5111 comes to life!

[old_coot88]

Originally Posted by Tubejunke

...Last night I did try adjusting the color killer pot and could easily see that it definitely needs cleaning by its somewhat erratic reaction. However, no matter what adjustment I made I never saw an actual color picture. When I turned it up (or clockwise) I would get what I would call color bleeding into the black and white raster, so I turned it back down.

Try this - turn the color killer back to where you get that "color bleeding" and leave it there. Keep the front panel Color control to maximum. Adjust the fine tuning to the point where the color "should be". The 'bleeding' that you see indicates the chroma signal is getting through to the demodulators, minus the 3.58 referance signal from the oscillator. I.e., the oscillator is not running.

The following applies more to RCA and RCA clone sets, so I'm shooting from the hip with an "educated guess" that it is applicable to Zeniths also.
Before messing with the crystal, find the "reactance" coil and check it for continuity. It is a slug-tuned coil with a single winding (no secondary). It's the 'color sync' adjustment used for locking the 3.58 oscillator. This coil was prone to going open intermittently from thermal expansion, or staying open, causing the osc. to not run.

If you had good color and it was strongly in sync (no barberpoling), I would be less prone to suspect the crystal.
Bill(oc)