Hornby R2066 Class 4F: Repair Request

I was asked by a chap called Steve if I could look at this old Hornby 4F. It was said to be smoking from the tender and not running well. So I agreed to take a look and see if I could sort it and to open up to doing subscriber repairs again. Just maybe less frequently than I was and be a bit more selective. So if you're in the UK and have a loco you'd like to send to me to repair or service, then email me via the About tab on my channel. I can't take them all or answer everyone. Also I am reluctant to accept Mainline or Replica Railways models so please don't ask about those. Please tell me what's wrong with the loco and include pictures. Cheers https://ko-fi.com/00bill73561