Diesels on Heritage Lines before Preservation

There's a brief glimpse of a diesel going past Trimpley Reservoir on the SVR in this 1967 news clip. I wouldn't like to guess what it is from such a low resolution distant shot.
https://www.macearchive.org/films/midlands-news-05051967-pumping-station-opened-trimpley

 

D7029 towed 80079 from Barry to Kidderminster in the 1970's and pushing it slightly but the 50's, Westerns and maybe the Warship based at the SVR must have worked through Kidderminster at some point.

 

Not just on the standard gauge section ...

http://www.kerrstuart4415.org.uk/

 

The Ffestiniog has two operational diesels which worked on the line before preservation, although to be pedantic I don't think either were actually diesels before preservation

 

And whilst on the narrow gauge in N Wales the Llanberis Lake Railway's pre preservation predecessor, the Padarn railway had a Hardy Motors IC locomotive - http://www.penmorfa.com/Slate/padarn-railway.htm (scroll down to find it - you won't miss it!)

Steve B

 

What a great little site. I can see me spending an hour or three looking at all the linked pages.

 

Looks like a Class 20 - possibly a local trip working using LMR based traction