On tbe gearbox appears a stud, which is one of two points that secures the foremost part of tbe chainguard.  This stud is front bottom.  On loosening the nut on this stud, it began to bind and caused the stud to screw out with it.  A closer look revealed, that gearbox oil was also leaking from that point.  Is this normal ?  When I screwed the stud back in, it seated, the nut loosened and was again, able to secure the guard.