Problem With Washing Machine Belt Keeps Coming Off

Hi

Ok, I thought I had fixed my Hotpoint washing machine but it turns out I have not. It stopped spinning during a cycle (although the cycle always completes) so I took the back off and noticed the belt had come off.

Following the online video instruction I put the belt back on. I put a load in and tested it and it was working fine. Then part way through the cycle I heard a noise and it stopped spinning so I took the back off again and noticed the belt has come off again.

So, rightly or wrongly, I thought maybe a new belt would help so I purchased one and when trying to put it on this time I could not because the wheel at the back of the drum will not turn to enable me to do it. It is really stiff, unlike the first time, I can get some movement if I really tug on it. I am confused as this moved freely the first time I replaced the belt.

Everything else works fine.

Help please! any ideas?

Further to above. With some force I have got the belt on and the wheel now turns. Problem now is when I gently turn the wheel with my finger you can see the belt slowly and gradually moving off it, moving off centre to the wheel and towards the edges.