Locomotive Update January 2013
Winter maintenance has now started at a pace with both sets of valves and pistons removed on Wednesday 2nd and Saturday 5th respectively.
The engine has been off beat for sometime and at certain times steam has been roaring up the chimney when trying to move the engine. This all suggested a valve ring(s) blowing by. In reality what we have found is the right hand rear valve rings had become damaged and loose so was certainly passing steam, which would have given the engine the off beat sound. On removal of the right hand piston we found broken piston rings. This may well have happened though as we removed the piston as it dropped out with a bit of a bang, as the front cylinder cover was being decidedly stubborn to remove.
Today (9th) we have stripped both valve assemblies and cleaned all the various parts whilst removing all the wide and snap rings that go to make up the valve head. In the next few days or so a contractor is coming to Toddington to bore out the valve liners in the cylinder block to remove any wear that has taken place. They will then take the valve assemblies away and manufacture new wide and snap rings to fit the new valve bore and fully reassemble the two valve assemblies. These will then be returned to Toddington.
The plan is we will refit the valves etc as well as refitting the pistons, with new piston rings and generally get the engine back together. In the meantime the tender coal space has been cleaned and Clive Norton has given it a first coat of bitumen. There are also various other small jobs to be attended too and we have to achieve all this by the end of next month so the pressure is on to keep the job moving.
This coming weekend the cylinder drain cocks will have to be removed to allow any machining swarf from the valve reboring to be washed out. If it gets into the drain cocks it could cause significant damage to them so prevention being better than cure? Whilst off they will get stripped cleaned and re-assembled ready for refitting.
One saving grace about having to do this work is that when the engine stops for her ten yearly overhaul this is one piece of work that will not require doing again at that time, at least we hope so.
I have to say so far volunteer turn out to help with the winter maintenance has been excellent, fringing on exceptional with almost more bodies than work. However we can always find you work so please keep attending in this critical period otherwise we will not have any engines for the start of next season as all three engines are having some heavy repair work this winter.
Well the work reboring out the valve chests has been completed and both the valve and piston bores have had an initial clean and oil up ready for when the new parts arrive. Stewart from Tysley did a really good job boring the valve chests only taking out what he had to in order to get the bore’s round again. He has also taken the valve spindle assemblies back to Tysley with him for them to fit the new rings and generally reset the valve heads on the spindles.
Our thanks go also to Neil Cooper of the GWSR who not only sorted out the air supply for us but also provided a small hot air blower which provided some level of warmth. Wednesday was even colder so the Wednesday gang had a brazier going which gave out a much welcomed level of warmth.
Our plan was to refit the piston’s on Saturday 19th but as I write this snow has descended and we have been unable to collect the new piston rings from Tysley. Hopefully this snow will not hang around too long as we really need to crack on with getting the engine back together.