<VV> Charging AC

[Smitty Smith]

Smitty says:  I am changing my wagon system over from 12 to 34.  I have a new comperssor and dryer.  System has been flushed and air dried.  Expansion valve has been removed and cleaned.  System was made up of junkyard parts except for the evap which is Early Corvair.  It worked fine on 12 till last summer.
  Upon charging systen it was drawn down to 28-29" which it held without loss for a half hour.  Charging it, I can only get about a can and a half of 34 in it and the compressor locks up.  Belt is a little too tight if anything.  IDEAS ???