There is an "inspection?" hole near the top of the leg. I took the cover off and with the vacuum cleaner on blow it runs fine so I am now convinced it is the exhaust gasket which Nos4r2 suggested.Thanks Nos4r2, and thank you to you all tto for giving me some ideas in solving the prob out.
All I have to do now is work out how to take the leg off
I do have an "online" manual but it'snot too clear. So fingers crossed for me please and if you are a Christian like me prayers would be well accepted.
Thank you all and I will keep you updated.
High Regards and blessings to you all