A shorted turn wouldn't necessarily make a big difference to the dc ohms readings, but if there's a shorted turn it ought to be possible to 'feel' it:- if you spin the generator with the output wires open circuit it ought to spin freely (don't know if your generator normally has cogging or not, but even if so, once it's spinning it shouldn't have much resistance).
If there's a shorted turn it will cog, (or cog more than usual) and if your trying to spin it fast it should drag and slow.