I tried with wd40 after reading some forums, i dont get what you mean with the wire for back door. The handle is on it just has no tention (really loose).
Yes his words were "this is really worn i will have to do it by eye" he has told me since to take it back so he can retry.
I will try the wooden wedge one in the morning thankyou. If that works i will just buy whole new lock set.
Any other help would be amazing. Thankyou