Electric Lawn Scarifier (Chieveley RG20)

Really efficient when it works. But it was rather gummed up when I tried starting it this year and now sounds like the motor's turning but the hooks aren't= broken belt? But I can't see how to get in and look at it even if I wanted to. But if you're into fixing such things...
Qualcast I think.
Advertised previously on Newbury with no success.