Dcc Ready Farish Class 47 "Stuttery" Running Problem

[Ray Von]

I've had this BR class 47 in storage a while now, bought 2nd hand. 

I noticed on first running, some years ago that it was a bit "stiff" despite being a relatively new model - I took it to a local model shop (now defunct) for a service and it was improved but not as good as it should be.

 

Fast forward a few years and I've started to use it again, but compared to other loco's on the layout it's really "not right" - it stalls and is jerky, also it completely cuts out over (insulfrog) points, despite spanning them quite adequately. 

 

I would like to know if there are any links here where I can get a service / mot on this unit, for the going rate?  I live in Margate so if anyone is local willing to have a gander...?