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The explanation of ‘K4’ The Great Marquess’ failure on October 23 1997 due to a wheelslip inside Bewdley Tunnel in the article ‘Will ye no’ come back again?’ (SR464) is incorrect. I was the driver on the day in question, and there was no wheelslip, as the train only consisted of four BR Mk 1 coaches - well within the capability of a ‘K4’. As the day was drawing to a close, we travelled along the Waterworks straight with steam on, but on shutting off we felt some big vibrations through the footplate, as if the engine were ‘off the road’. With light steam applied again as a cushion, the vibration and noise ceased, allowing us to make a controlled stop near Sterns Cottage. The engine was examined, and I found a slightly polished area on the inside cylinder piston rod gland. The inside big end bearing, however, was intact. Where the locomotive had stopped, the righthand side coupling rod was adjacent to the wheel balance weight, with about a one-inch gap. Crucially, I noticed that the coupling rod had rubbed the balance weight, thereby wearing away the black paint to reveal the apple green beneath. When I examined the left-hand side middle driving wheel, this revealed cracking of the paint where the stub axle is pressed into the wheel pan. I called Bridgnorth works and explained the findings. I suggested that the locomotive should move, as there was no noise with steam applied, which is what we did, at walking pace. Upon arrival at Bridgnorth, the locomotive was uncoupled from the train and examined under movement, which is where it was declared a failure. The cause was attributed to valve setting, where the inside and outside valve gear were fighting themselves, via the conjugated valve gear arrangement (as fitted to this and other three-cylinder LNER locomotives). This, in turn, had applied a slight twisting motion upon the crank axle, and weakened its integrity over time. In fact, drivers had been struggling with the screw reverser for some time before this date. So there we have it, no wheelslip and several runpasts after the so-called ‘terminal failure’. That it seems we shall not see and experience No. 61994 in action again is a great shame, as it is an ideal main line and preserved railway locomotive, and a unique example to boot. Fortunately, I can say that I have worked on its footplate both on the SVR and main line over thousands of miles in the past.