[Heathkit] SB-101 problem

[k1mcn- at verizon.net]

I have a SB-101 that I am restoring and have run into a strange problem during the alignment I was going to adjust the idling current and found that when I keyed the microphone the output of the rig went from 0 to full output. I traced the problem I think to the double balanced mixer.
It seems to have a carrier output even when there is no audio going to the mixer. I have replaced the diodes with matched 1N191's and tested all of the other components in the mixer. I also checked to see that the mode switch was only grounding on side of the diode ring when in tune and CW.So far I have had no luck in getting it not to put out a signal when there is no audio.

>From the circuit description in the manual there should be no output if there is only the carrier oscillator is that correct?
Has anyone run into this problem or have any ideas?
I appreciate any help.
Thanks,
Matt