Radial arm drill

Had a an interesting call this week a Fabrication plant. This unit is a Mother of drills, there could be bigger. Fault being dead unit blowing all fuses in-side, external and tripping the RCD protection. Looking like another dead short. After few minutes of testing located the problem to be a 2 inrush diodes. The drama is to be continued, replacements ordered, but I suspect there other faults this unit yet discovered .