(HELP WANTED) Silver Fox A class bogie issues

[Liam Kett]

My silver fox A class is having some problems. The motor bogie seems to lock when running causing derailments. Just womdering is there a fix or did anybody else have this problem

[jhb171achill]

Some of them have different types of bogies, I think. Do you know what type it is?

[WRENNEIRE]

Some pics might help
Also the body on these locos are glued to the chassis, check that it is still glued correctly and has not loosened .

[TimO]

You say that the motor biggie is locking. 
Does this happen on straights or curves or always at the place on your layout?

Does it happen when travelling both backwards and forwards?

Have you turned the loco over and looked to see if you can see anything that might catch?
I have a C class where the glue holding on the bogie sides formed a glue string that acted as a brake and prevented the loco running properly in one direction. 
 

As others have said, more information would be useful. You may have to separate the body but as it’s glued on this is not a very simple task.  Let us know how you get on.

[Liam Kett]

Thanks all for your concerns, i somehow got the body off and saw that the weight would clash with a small piece of the bogie, so i moved it and sanded the frame around the bogie a tiny bit, she runs great now. Thank you all its great for a young modeller like me to have support