For all of my lifetime, certainly my time aware of railways, mainline diesel locomotives have been powered by a diesel engine driving electric traction motors. However the Western region was never really one to follow what everyone else was doing and invested heavily in Diesel hydraulics. Of those the largest class and the only one to fit into the type 3 category were the Hymeks of which I missed out on. When I was born there were half a dozen still in service and they were withdrawn before I had transitioned from a 4 legged human to a 2 legged one. So they are all a bit alien really.
Apart from the transmission (and the idea of a mainline loco with gear changes) there were other things that were a bit odd. Why wasn't the radiator fan housing central? Why didn't they use no.1 and no.2 ends, Instead of having A and B and why was the radiator at the back not the front like everything else? Despite all the weirdness they were attractive little locos though so when a Heljan one popped up cheaply on Ebay (described as having intermittent running) I put in a cheeky bit and as no one else did, a Hydraulic is coming to Brettell Road.
Not having any 00 track I didn't investigate the reported running problems but the Heljan wheels were filthy and having swapped them out for some Alan Gibson ones no running issues were encountered. This model is one of Heljan's early efforts and in terms of getting the shape right still one of their best. However there are a few tweaks that can be done. The roof horns were broken so they were replaced with Markits brass ones. The buffers were a bit naff so those were replaced with Lanarkshire Models ones. The numbers and builders plates are from Shawplan/Extreme etches. The rest is really down to working with what Heljan give you. The bodyside windows are flush glazed but not flush enough so they were cut out and remounted. The cab side and door windows are fine but I did add the droplight strips from 10x10 microstrip.
Not much to do on the chassis really - I added the mileometer on the leading axle of the B end (left) and I thought the pipework on the bogie frame at the A end was a little too fine so replaced it with wire.
This is the A end from the other side. As I was doing an early batch loco I carefully cut off the headboard clips and touched in the yellow. The windscreens were also not flush enough but it was easier to just replace them with clear plastic cut to shape. Oddly the glazing on the headcode box (yes i know the headcode is wrong for the train) was too flush so this was replaced as well. Windscreen wipers are again from Shawplan and the brake pipes are from Hornby (the loco wasn't supplied with any). I also remounted the tank under the bufferbeam and added a little pipework. To avoid confusion when it comes to DCC I've followed the diesel electric convention and set the fan end as forward.
The model is weathered to look new but not 10 yards from the factory new. Im aiming for a few months and bear in mind the layout is set in autumn. There seems to be a tendency among modelers to weather Hydraulic locos to look an absolute state and most of them did end up that way in real life. So basically washes that I've pretty much cleaned off again as best I can before light dustings of track colour and roof dirt. This was followed with streaks from AK interactive spilt fuel and grease before finally the obligatory rain effect. Diesel locos tend to have characteristic weathering which is unique to each class (something which a lot of professionally weathered locos you see seem utterly devoid of). Class 24 to 27 have the water stain from the roof, just inboard of the fan. Class 50s have 3 leaks that run down the fuel tanks, class 20s have an odd direction for the staining deposits from the exhaust and class 31s have the oil leaks through the bodyside at floor level. Hymeks have this too but not as much and from my research only later in their (short) lives. They do however have a distinctive leak on the fuel tanks and this seemed to have been from new.
Any reason for D7022? Ive always had an affinity for the Lickey incline and these 3 locos were all regulars on banking duties over the years. The Hymeks went there much later than Brettell Road is set and were the second class of diesel to work the incline. The first being English Electric type 3s (class 37). A lot of Hymeks worked the Lickey but the initial ones were D7021-D7025. In his book, A life on the Lickey, Pat Wallace talks about them and mentioned that early on they preferred to have the A end facing north (up the gradient). If a loco turned up the wrong way round it was sent to Worcester to be turned on the triangle. He doesn't give any detail on why this was the case but you could lock out first gear in a Hymek and the equipment cabinet for this was in the A end. The locos definitely had first gear locked out while on this duty. This was because the change from first to second gear was right in the range where trains were banked and they could snatch. The Hymeks having only one engine were a little worse for this than the Warships and Westerns.
One little anecdote Pat also mentions concerns the 17th January 1968 when a kitten was discovered in the engine room of D7025. He was adopted and named Hymek (of course). He crops up again 10 days later when he had managed to hide himself in the bogie of D7022 and refused to come out. It was reported that Hymek the kitten did 4 trips up the Lickey!