Retention Vs Track/Underframe Dump, hmm.
They both have they're up and down sides from a Maintenance point of view (Well, my biased one anyway!

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On the old Slam Door Stock, it was pretty disgusting underneath the train around the toilet areas, to put into perspective, it was more white (and brown) toilet paper than brake dust/grease. :cry: As The Slash will probably testify, When Examing No.4 Motor on a 4CIG, you had to scrape off a fair inch of "The Brown Stuff" before you opened the Commutator Cover to inspect otherwise you'd get a face full of it, and believe me you'd only do that once!
142's, 150's and 153's etc are a different kettle of fish on the other hand, because they don't carry 750v equipment under them, they have routine underframe cleaning where most of the horrid stuff it pressure washed off, which makes it more pleasant when working underneath. And Ive much rather have that than a rentention tank stuck underneath ponging out the sheds and in some cases leaking. :cry:
A Good example is of a 319/2 before they were Refreshed with Southern had the Disabled Toilets locked OOU for a long while, thus the water in the U Bend had evaporated and you were left with a nice air vent from the Retention Tank into the Toilet and "Airing" out into the saloon! :roll:
So my view? Track Dump's better if the units can be underframe cleaned. Plus theres less of a chance of having a pongy unit! (Anyone whos been in a Voyager Vestibule will know what I mean!)
Besides, would you want to be the operator that sucks out S**t from Retention Tanks? Thought Not.
