TC reported MCH was stuck at B3. Unableto proceed in ATPM. Proceeded in Auto mode to next station.  ~~~~~ TC reported MCH was stuck at B3. Unable     #719 MS mounting bolt improper tightening causing wheel slot to be unable tp positively engage.Loosen the 2 bolts and carried out balance tightening and torque to 5.8Nm.Carried out MCH function test in all modes-ok. Done by Joshua. 18/03/20