Which action correctly addresses a soft foot condition on a motor mount?

• A. Shims all four feet
• B. Tightening all bolts
• C. Replacing the mount with a new unit
• D. Shim one foot only

Answer: (D)

Soft foot means the motor frame isn’t sitting on a perfectly flat plane because one or more feet aren’t contacting the foundation properly. The fix is to restore a true plane by shimming the feet that are short until all four feet touch the base and the mount sits level. In many cases only one foot is short, so placing a shim under that foot brings it into contact and eliminates the twist or bending the frame would experience when the bolts are tightened. This approach ensures the shaft and alignment stay true and vibration is reduced. Tightening all bolts won’t cure soft foot because the issue isn’t loose fasteners—it’s missing contact with the mounting surface. Replacing the mount is unnecessary unless the feet or base are damaged. So, adding a shim under the appropriate foot to achieve full contact and level footing is the correct action.