It was listed on eBay for spares or repairs. I originally intended buying it for spares but there was something strange about the boiler so I asked the seller for more photos. Of course that increased the interest for this loco so I got it at a much higher price than I'd anticipated.
A riveted boiler back plate.
It was an early SL3 (key ring type coupling ring and no bulge on the smoke-box sides for the tank tabs), but was missing the wheels & coupling rods plus fixings, chassis spacer, screws and nuts holding cab sides to chassis frames, safety valve (a bolt with thick washer was fitted instead), rear drag beam including buffer beam plate, buffers & coupling ring, and had another screw loosely screwed into a hole on the bottom of the boiler.
After the fitting of wheels, rear drag beam, a safety valve and a water top up valve which replaced the removed whistle.
I've seen these crude screws fitted to the bottom of other Mamod boilers but never really found out why that was done. I guess it was some form of boiler drain plug in the days before syringes were readily available to the general public. So I soldered a 6BA screw into the hole using plumbers solder which does not melt in the flames of a meths burner. The whistle insert was leaking and I tried to repair it using a solder tip on my gas torch but that did not get hot enough to melt the solder paste so I had to use the hot flame adapter. Despite using wet towels I still managed to damage the paint on the front of the cab with a combination of this hot flame plus trying to get the whistle out in the first place. This process still did not fix the boiler insert completely so I had no option but to de-rivet the boiler back plate and smoke-box in order to remove the boiler for a full repair. I re-soldered the 2 boiler top inserts (the steam dome insert had been re-soldered by the previous owner and sits somewhat higher than normal).
Having de-riveted the boiler back plate I soldered in 2 x 6BA screws so I can fit the back plate using washers & nuts. The sight glass recently started to crack so on removing I found that the cut-out in the back plate had a rough edge where the crack had started so I smoothed that rough edge out and fitted a new sight glass.
This loco also lost its reverser valve when I was trying to get an SL1K ready for re-sale ( http://gardenrails.myfreeforum.org/about423.html ). So as I was going to fit a refurbished reverser valve I decided to de-rivet the cylinders as well, fit new gaskets, hone the cylinders and refit. On checking the alignment of the steam holes I found one cylinder had the front steam/exhaust hole in the wrong place but fortunately the cylinder end caps are the thick variety so I managed to fit the front end cap where it sticks out a bit but is steam tight and does not block the misaligned steam/exhaust hole.
I like the brass balloon chimneys and decided to fit a silicone tube to the exhaust (bending the short straight pipe to shape).
This loco has always started off with priming and runs with a wetter than normal exhaust. This may be due to either the raised steam dome insert, or the condition of the boiler inside. I've just soaked the boiler in vinegar for 2 days which seems to have cleaned up inside a little but I forgot to put the exhaust pipe in the back of the reverser block when I re-assembled the loco so it has just run with no proper exhaust pipe. Need to wait for it to cool, refit the exhaust pipe and then compare how that priming has progressed.
Refurbished boiler.
Screw soldered in to plug the drain hole.
The loco is missing a couple of items so I will put up a Wanted request for these shortly.
Chris Cairns.
