Does it matter if tender valves pass a slight leak?

Hi - I have made up a couple of tender water valves for the injector feeds on a 5"G locomotive and bench tests carried out on the valves with a head of water equivalent to the full tender height show a small but persistent leak. My question is - Is this of significance and what are the consequences of the feed pipes leading to the injector inputs filling up with water leaking past the valves?

Lots of drivers in our club leave the injector water valve cracked open all the time. It keeps the injector cool, and there is then full water supply available the instant you whack the steam on

Duncan - Thanks for your reply. It means that I can live with my present valves with some reassurance that they should be OK in practice.

Firemen on heritage railways usually get an ear-bashing from the inspector for wasting water if they do that.

Brian,

I took the ear bashing with pleasure. The damn inspectors don't have to douse the injectors with buckets of cold water to get them to work! Pity, as otherwise they may change their tune.

Andrew.

Worth considering if the leak is internal or external though? It's fine if there is a small leak through the valve but if it is leaking up the stem through the gland you stand a chance of sucking air in when the injector is running, and they don't like that!

Paul.

As Paul says, if the valve is leaking when shut off it is likely that, when using the injector, it will pull air into the water feed line causing the injector to fail.

Pete

I had injector feeding problems once with a 5" tank loco. I traced the problem to a leak in the feed pipe from the side tanks. Not big enough to show with the head from the tanks but enough to allow air in when the injector was trying to feed and the vacuum was drawing in air. Cured the leak and the injector worked fine.

Edited By Andrew Binning on 27/06/2020 08:53:19