Advice please knocking loco

[sandy]

I have a Hornby R2742 Class 5 Charterhouse DC ready. She runs fine forward and reverse but running in both forward and reverse there is a knocking noise. I am wondering if it is a gear problem. Any ideas.

[Walkingthedog]

Could part of the connecting rods be catching.

Can you test the loco off the track with a power lead or battery?

[sandy]

I have spent a long time checking the con rods Brian and they seem to be fine. Have run it slowly loco in cradle and can see every thing is OK with the rods

[Walkingthedog]

Do the wheels turn smoothly, not rocking from side to side for instance.

[sandy]

Other than the knocking noise the loco runs perfectly. Think I will send it off to Hornby repairs.