John New I really doubt it's a short circuit issue as the chassis and body work are all plastic and the couplers aren't attached to anything else made of metal.
John of the Aussie variety I am using graphite, even I'm not daft enough to not use it.
You're right Steve, it wasn't tamped down I just dropped it on it then used my finger to get it to shape. However I have already been getting rid of stray ballast and glue, the layout didn't even run until I did that.
I've actually found the source of one problem and that was some stray paint from the track painting, getting rid of that has solved the problem for one area however the other area still isn't quite right despite me removing the paint on the insides of the rail and getting rid of any excess ballast.
Still I've been able to reduce the power needed to get through that section reliably to around 42% (it sometimes goes though at 30% but not always) so that's an improvement. Although it's now up to 50% again as I've added a large chunk of lead to one of the wagons, the lead can be removed if needs be (it's hidden in the tool box with the hinged lid I made last year).