very probably it got a bit damp, This alters resistances in the cicuitry and changes which coils rceive the current first vitually reversing polarity. ( I know we are tajking a/c not D.C. but it's the easiest way to explain it) This is a very rare occurrence as damp normally shorts out the machine blowing a fuse in the process. More often than not when dried out' or even dried out by the heat generated in the shorting out. the tool will run ok again . Sometimes not and a rewind is called for or scrapping. Rwinding usually far too expensive Unless of course you've got deep pockets and love affair with the piece of kit. (Very Rare or something) this is just my thoughts on it but ssomeone else might say "what a load of old tosh" Well for what it's worth that's it . Cheerio .
John Mantova, April 2012
