First thing you do is to ck for compression. If seal is "done for" you're looking into rebuild it yourself or buy another one.
Thing about rex is that electrical is much to be desired and ck for harness for brittleness and be sure to ck the inside of oil cap. By doing so you can generalize what's going on i.e., coolant seeping into oil, etc.
Rotary is one great engine...if you take care of them
