Despite the rumous of the imminent arrival of the bearded one, we sneaked an extra work day into December 2013 just because we could! The task force were assigned basically two key tasks: attempt to fix the 3rd and closest to the cab safety valve and remove the rear engine cylinder covers.
Prior to any work though, the workshop did need some tidying up and general housekeeping. Many people using all the tools and equipment over the many work days results in each having their unique opinion on where the said tool should reside when they return it! The tools and equipment were spread across the floor and over the benches. A few hours and some order had returned although the location of some groups of tools may not seem appropriate to some, at least all the hammers were in one spot!
Over to the rear engine and with some persuasion and correct selection of wrenches the valve end covers were removed. These are much lighter than the cylinder covers and relatively easily managed by two people. The cylinder end covers are a much more different kettle of fish so once undone they were unceremoniously pushed off and allowed to land on rubber matting.
Good news - the bores were not covered with any possum poop or rust, a testament to the great sealing job done on the cylinders many years ago.
The safety valve was deemed to be in need of seating and grinding to make it seat – during the hydraulic test it was noted to be weeping. After some effort and grinding the valve was replaced to wait testing at the next hydraulic test.
There was however A HIDDEN AGENDA behind the extra work day one – it was to move the pistons and valves to the workshop.
Some say that these items were a myth and had been lost in the mists of time in some TARDIS like van, long since lost but as with most myths (and lucky for us) they are false. There they were safely tucked away in the end of a guards van, 4 cars from the end of the road. Safely hidden under fold down bunk beds and assorted paraphernalia they were heavily disguised. Heavy (about 250kg per piston) and not easily moved three of us managed in shifts to move the 4 pistons and 4 valves to the workshop. There they celebrated Christmas and New Year’s.
January 4, 2014. Welcome to 2014 - The New Year’s first work day saw a great turn out of volunteers. Most seemed nonchalant about the fact that the pistons and valves were now out in the workshop but silently there was a level of excitement that the realisation that the project was about to enter a very critical and important phase.
The teams divided into a number of groups. The first group tackled the studs on the cylinder ends and valve ends. The hind engine was addressed first – probably because it was closest to the workshop! The valve studs were all removed cleanly and without major drama. New studs will be replacing the removed ones after checking the internal threads in the valve casing.
The cylinder end studs were a totally different job and technique. Most were looking in poor state and seemed to be requiring replacement. Heat treatment on these studs did not produce the desired result so a strategic decision was made to re-thread the studs and have them assessed for strength and integrity. This will be done at a later date. The work was exacting and difficult and took all day to end up with a successful conclusion to the work on the rear engine. A great effort and it does make the same work easier to perform on the front engine now that the technique and results are known. This is a job for the next work day – Sunday 19 January.
Another group started work in the cab. The third safety valve was once again removed but instead a replacement valve was located in stores – a van of Aladdin’s delights stabled down the track. The replacement valve was disassembled and inspected, rebuilt and then mounted on the boiler. The next few hours were spent seating the valve in with grinding paste. Like painting it is not a very glamorous task but extremely important to get right and besides, the view from the top of the boiler did provide some benefits for the long time spent grinding away.
In the cab a number of valves and handles needed significant work to ensure a correct seal. This required grinding and in some cases machining. Also while this was going one a new metal floor plate was being fashioned. This was required to cover the area on the floor of the cab where the coal auger rises up to meet the firebox. Thick steel plate had been obtained and after many measurements was cut to size. Interestingly the measurements showed some considerable differences in length from the back of the fire box to the respective ends on each side of the auger. Nothing major and in the end a great piece of skill and craftsmanship resulted in a near as possible perfect fit.
The remaining group of volunteers proceeded to make themselves as dirty and grimy as is humanly possible by holding 4 inch grinders in both hands and applying the wire brush ends to the caked and baked-on oil that had adhered to the valves and pistons.
The first items tacked were the valves. The main concern was the valve stems. There were no visible problems shown so these were polished and re-stacked onto the pallet.
The pistons presented the challenge. Whilst no one will ever see these again once they are back inside the cylinders there is a sense of satisfaction in making that metal gleam again even only for a short time until the next service. To get to this state though the oil that had accumulated whilst in service had become diamond hard and required chiselling and hammering to loosen. Wire brushes visibly wore down as they were applied to this material resulting in two errands for replacements brushes being made to the local hardware store.
The photos tell the tale though, and there are now 4 pistons awaiting the next steps – transport to Sydney, machine down, build back up with electrolysis application of a chrome layer and then machining back to correct dimensions. Specialist work and as maybe guessed expensive.
Lastly the ever present need for the rings – these need to be manufactured. With the pistons cleaned and before they travel to Sydney accurate measurements of the diameters and widths will be made. This is an exacting task that requires patience and skill.
Naturally measurement is one thing ordering and paying for the rings is another – please see how you can help. The rings are the major last hurdle to conquer and we need all the help we can get - big or small.
