I think it was operator error.  i didn't understand how the controls worked.  I did get everything to work once I saw how the channels (or signals) were being routed.  It sounds great.  Dirtied up the signal and got a pretty rich tone.  I have all fender amps, this is my nephews Marshall.  I want to spend some more time with it and enjoy 'that' sound.  I have a friend that designed and built his own amp.  One channel has as Marshall preamp design and the other a Fender (Tremulux).  That's a great sounding amp - mix, single channel, lots of possibilities.
thanks again for all the help.

I replaced the 134 with the Buz 901, the amp is working now.  The output is controlled by the volume switch VR9, however the 'gain' pots VR 1 and 2 don't do anything.  It seems that part of the circuit isn't working.  There's good clean sound coming out of the speaker with lots of volume.  I'll poke around the 'Gain' section to see what isn't working there.   Any ideas on how to approach that? 
I feel lucky that I only had to replace the 134.  I thought I'd have to do both (I have both), but can't argue with success.
Thanks for all the help. 

thanks for your response.  I've done a little more checking around the output stage, measuring static component values and found that the mosfet 2SK134 had a short from the yellow wire to the blue.  I 've ordered a buz 901 to replace it with.  I hope that will be a 'drop in' replacement.  From what I could tell all the other components seem to be okay.

I'm a newbie to this forum.  I just finished a successful build of an old 5E3 tube amp, now I've taken on my nephews Marshall Mosfet 100 amp repair.  I got a schematic off the web.  All the voltages appear correct.  I followed the signal path to the power amp stage, which begins with a couple of A06 transistors.  The transistors in the pwr amp stage seem to pass the simple transistor test.  Is there a way to test the power output transisitors?  Any ideas on how to find why the signal disappears in this part of the curcuit.  Thanks for any help.
schematic      http://www.drtube.com/schematics/marshall/3210-iss7.gif