I have recently inherited an Atco Commodore B20 which has been 95% restored and is a lovely condition. However I have an issue with the toothed belt that drives the cutter (it's one of the later Commodore models), similar to that shown below:
When the belt tensioner is NOT in place, and I rotate the cutting cylinder by hand, the belt remains in a straight line and stays in place. However, when I install the tensioner, the belt drifts outwards and ends up rubbing the inside of the intermediate drive chain - obviously, the belt would not last long before it shreds!
I have tried bending the tensioner slightly to try and keep the belt in line, but to no avail; it just keeps on drifting outwards.
Is this a known issue, and is there any suggested remedy?