electric saw problem

soho

i decided the other week to pick up a cheap second hand electric 1800W talon, and so far it's turned out to be a total waste of time (i know, i should have known better)...

here is a similar looking one:



i purchased the saw just to use around the home to clean up smaller bushes, rather than get my larger partner saw out all the time... i figured it would just be a light and easy alternative...

so i was cutting some small branches etc, and came to a slightly larger, but by no means big branch, of about 10cm diameter, when the saw malfunctioned... the chain simply stopped spinning... i took the thing apart, but the make up the motor is a bit unfamiliar to me, as its completely different looking to a regular motor... with the chain and bar removed, the sprocket will spin. but when the chain is on, the motor goes into a high pitch squealing sound, and the chain wont spin.

it seems like there is a disconnect somewhere, but i cant seem to work out where it is, or how to fix it...

any help would be great guys... otherwise im just going to cut my losses and throw the thing out...