well you guys got most of it working for me,now the problem is i have great shortwave,but when i switch to a.m. the radio is dead.did notice that the voltage on speaker transformer is 240 volts when in s.w. but drops to 11 volts when switched to a.m...where do i start looking.

When we last tuned in, your set had a hum and the B+ and B- voltages were unaccountably swapped.

What was done to the set to resolve these two issues?

:When we last tuned in, your set had a hum and the B+ and B- voltages were unaccountably swapped.
:
:What was done to the set to resolve these two issues?
:rechecked the electros and rewired .now have all correct voltages on s.w. but very low voltages on a.m...the tone ,bass,normal switches were cut and i have not reinstalled these yet,also the push buttons for the stations was cut and have not been installed...could this be a problem.

Yes.

:Yes.
:the tone controls and station push buttons are now hooked up and same problem dead on a.m...

Tone control wiring doesn't matter, assuming that you didn't introduce a new problem when hooking it back up. Does the set not work on both AM manual or automatic (pushbutton) settings? My guess is that you have a bad oscillator coil or miswire in that coil stack. Not knowing exactly which wires you removed, I can't narrow it down further than that.

You can troubleshoot the low voltage condition, however, just by tracing it back to the node where the voltage turns good again. Then look around at the low-voltage node to see what could be drawing it down.

:Tone control wiring doesn't matter, assuming that you didn't introduce a new problem when hooking it back up. Does the set not work on both AM manual or automatic (pushbutton) settings? My guess is that you have a bad oscillator coil or miswire in that coil stack. Not knowing exactly which wires you removed, I can't narrow it down further than that.
:
:You can troubleshoot the low voltage condition, however, just by tracing it back to the node where the voltage turns good again. Then look around at the low-voltage node to see what could be drawing it down.
:
:the low voltage starts at the speaker transformer when in a.m. ....the voltage is good at speaker terminal when in s.w.
:

::Tone control wiring doesn't matter, assuming that you didn't introduce a new problem when hooking it back up. Does the set not work on both AM manual or automatic (pushbutton) settings? My guess is that you have a bad oscillator coil or miswire in that coil stack. Not knowing exactly which wires you removed, I can't narrow it down further than that.
::
::You can troubleshoot the low voltage condition, however, just by tracing it back to the node where the voltage turns good again. Then look around at the low-voltage node to see what could be drawing it down.
::
::the low voltage starts at the speaker transformer when in a.m. ....the voltage is good at speaker terminal when in s.w.
::
:
:on the n.a. schematic,electrolytic #c17 ,the - or + is hooked to the resistor r-16,still trouble shooting.

::on the n.a. schematic,electrolytic #c17 ,the - or + is hooked to the resistor r-16,still trouble shooting.
:
:
C17, C18, and C19 all have their negative terminals tied together and to the center tap of the transformer high voltage winding. So the positive terminal of C17 goes to R16.

:::on the n.a. schematic,electrolytic #c17 ,the - or + is hooked to the resistor r-16,still trouble shooting.
::
::
:C17, C18, and C19 all have their negative terminals tied together and to the center tap of the transformer high voltage winding. So the positive terminal of C17 goes to R16.
:well thats how i have it,the trouble shooting resumes.

Do a bing.com or google image search for Zenith 7S633 and you'll find some high resolution under chassis pix of original un-restored chassis. It might be helpful to see what the factory did compared to repairs and rewiring. Schematic is always best though.

:Do a bing.com or google image search for Zenith 7S633 and you'll find some high resolution under chassis pix of original un-restored chassis. It might be helpful to see what the factory did compared to repairs and rewiring. Schematic is always best though.
:still trouble shooting,have checked pics and my set is wired the same,still very good shortwave,no on am or am pushbuttons< there is still no voltage on tubes..have checked band switch ,seems okay.have checked this set with another 7s zenith set and all wiring looks the same.