OK, tore it down and inspected. found no problems. Clearances were perfect. Added a conical spring and rebuilt the shoe to make the head ride just right.
put it back together and problem is WORSE. Put logic probe on galil channels quite a bit. Channel A+ is not always putting out a signal - just intermittent. The worst kind of problem.
Time to quit putting good money and time after bad. The whole thing goes in the trash bin.
Can you suggest a complete scale compatible with Galil inputs?
PS got a magnetic read head and tape free to good home. there is a chance problem is elsewhere.