Can i ask is your hymek the latest batch or the oldest as the differance will be the old or new type wheelsets stopping her running if not the contacts.
As for the Heljan western.The latest batch on testing a few are noisy compared to last years releases for an exception of a few.
As stated elsewhere the lights are next to useless on dc operation but i believe the Bachmann warships to be to bright.
As for me my Heljan westerns are on borrowed time with the release on dapols version although saying that the Heljan one with a bit of work can be a real looking beast and can or should pull a ton.
Do thou check the wheelsets on the hymek as if the older either replace or give a good clean.
B end on a western i believe was identified on one body side only by a bodyside latch under the engine room window.
richard.