ColinB

Yes, exactly that the X8849 Merchant Navy intermediate gear is too big, whereas the X6346 A1/ Tornedo is not. I did wonder if gears were spread around the range, it is a shame that there isn't a site where you could look this up or some of the suppliers have an equivalent listed. Perhaps it goes against Hornby's terms and conditions. I suppose you need to find the "brain" in the spares suppliers, bit like when you walk in the Ford Dealer and there is an old boy that knows the parts off by heart and their equivalents.

This is just for information. I needed a gear train for my Hornby Stanier 4p. Hornby don't have them anymore. I was surfing the web and I came up on the RM chatroom where someone had exactly the same issue. Anyway somebody on there said the Hornby A1 gear train works and sure enough it does. The gear on the wheel is the same one that they use in many of their other locos. I did find the Merchant Navy gear train was too big. The good news is they still sell them, for some reason Tornado spares seem a lot easier to obtain.

In that case all you need to worry about is where to put the socket. I would recommend using a socket as it means you can use different DCC decoders easily. The other thing is, if it fails then easier to replace. So all you do is isolate pickup wires from motor wires and wire to the socket. On 8 pin, motor goes to pins 1 and 5, pickups go to 4 and 8. If there isn't room in the loco or you need more room for sound you can put the socket in the tender and connect using the Hornby 4 pin lead and socket, sold as aftermarket items. Before you put the DCC decoder in the socket, again where a socket is really useful, check for continuity between pins. You should get open circuit, except between pins 1 and 5 which will be the motor impedance. Put the converted loco on the track, and check pins 1 and 5 are not connected to the track. This saves you blowing up the decoder, I know because I blew up many when I first started. You can now put in the decoder and you are ready to go.

Yes thinking about it, I think there must be a heat dissapation issue with these modules. I replaced the TTS with a Zimo normal DCC module and it has been happily doing circuits all afternoon. I suspect it has got to be the motor driver as the one in the tail unit that doesn't have a motor is perfectly OK.

Yes, that wouldn't help. It is like it is pulling a load of carriages.

The TTS Decoder in my HST has just failed, it was running perfectly when it sort of slowed down, I did think that I am sure it used to go faster and then a few revolutions later just died. It now just registers as a short circuit. Now for once I did nothing to it, it was in the HST pefectly insulated, the only thing is today it is very hot in the loft. I suppose it is a return to Hornby, trouble is it must be about 6 months old. It can't be overcurrent as I know from bitter experience they basically smoke. Are they really that susceptical to heat? I suppose I will have to go through all my "on line" receipts to find a receipt for the return.

I have only just read this post, I too have had a lot of issues with points, I also have some reasonably old locos I run. The things I have had issues with are: On the older locos especially back to back wheel spacing, tender driven locos the centre undriven wheels not moving up properly. Sometimes some of the points (I use Peco electrofrog) if not supported properly warp, especially with the heat, in one case one turnout was 2 mm lower that the other meaning the point was not flat. The approach to the points was not flat and if you use fexible track had a kink at the point junction where if was trying to ping out (extra pinning cures this). Base board flexing beneath the point. Assuming it is not back to back spacing, is arm myself with thin cork underlay slivers, and pack bits of the track until it stops derailing. Then once you have figured which part of the track needs sorting out, implement a more permanemt solution. Oh I forgot on some locos, the front bogie causes lots of issues. Peco haven't really changed the design of their streamline point since the 1980's since I first started, so locos after this should run reasonably ok. Hornby points from what I have seen are similar to Peco Settrack points so most loco should work with them. Even my Wrenns work ok over most of my points.

I am not an expert, but if you think about it the Hogwarts Castle is going to be less sophisticated to the King, so everything will be simpler, so less strain on the motor so less current and less buzzing. I never looked at a Hogwarts express but it might not even have all the extra gearing a King has. The valve gear especially, so it could be that it buzzes now because the motor is doing more work. bulleidboy is absolutely right they do quiet down once they get run in, I had an exceptional noisy five pole tender driven loco I have just converted, after half an hours running in, it got a lot quieter. It is obvious really, all the high spots on the gears need bedding in. The only other thing I can think of, is the motor is not aligned with the gears, but mine failed within ten minutes, so from what you say yours hasn't, so it is not that. Funny, all I did was unscrew the motor and screw it back and it was fixed. I did do a test on my King and it is quite quiet but I am using DCC, and TTS and I am used to really old Hornby tender driven locos that are very noisy. I would have tried it on DC but I had to disable the DC option as the TTS used to go flying off, and I don't take newer locos apart unless I absolutely have to (it is so easy to damage something). The best idea I can think of is "run it in" for half an hour if it is going to fail then it probably will during that time, so you can return it as broken. I think half the probem is the controller, my DC one from a Pendolino set buzzes an awful lot with certain locos, there are even posts on this forum over that very subject.

It is funny that, I have converted all the ringfield locos to DCC, plus added pickup by both sets of wheels in the loco and on some changed the motor to 5 pole (Peters Spares has some very cheap motor units) and they are really good. Not as good as motor in the loco, but not that bad. I didn't even know Dapol had a pancake motor. Those locos are really expensive second hand. There is a review on You Tube that says that they are good, but I suppose it depends on your acceptance level. I have never done one of these, but if you are going to do it, make sure you don't use the Hornby DCC chip, they don't seem to be able to handle the "stall current" of ringfield type motors, use a Hattons (1.5 amps max) or a Zimo (0.8 amps max). I blew a couple of Hornby ones up when the loco stalled on a point (admittedly because I got the wheel spacing wrong), but it is better to be safe.

I just did a check on one of my cheap Chinese motors (if you read SAMS you tube video you will see what these are) which are roughly the same as Hornby fit in their locos. You get excess buzzing if there is excess load on the motor so there may well be something wrong.

Don't worry about the blanking plug, it wouldn't work without one so that is not your problem. I just think it is your controller. The Hogwarts express is quite new so it is going to be a PWM controller, so you will get some buzzing when you start up, it should get less the faster you go, if it doesn't then it is your loco. The buzzing will depend on the reaction between your motor and pwm of the controller. If it is easy then get who supplied it to check it out, they will probably know what it should sound like. The other thing to do is see if the valve gear moves smoothly, usually if there if a gear issue you should hear a slight click, but from what you say it is a buzzing, so if anything it is the motor. To check the controller you could put both locos on the same track placed suitably apart and see if the noise is less, if so then is it probably the controller. The other thing which is quite important is the blue King is not that easy to get, the dealers are running out, I went through many dealers trying to source one.

According to the ad on EBay https://www.ebay.co.uk/c/1357677986 it is loco drive, but according to the model rail database it is a ringfield motor. So is it tender driven (motor in tender) or loco driven (motor in loco)?

What DC controller are you using, is it one of the latest ones? I am assuming the loco runs as you say it makes a lot of noise. If you have got one of the new Hornby controllers that use PWM to control the loco, they do make a lot of noise on low settings. I did have issues with my one, but that was mainly the motor not being lined up properly, but in my case the loco stopped running and just made a horrible noise grinding noise. Once I fixed it I don't remember it making much noise, but I use DCC.

Does anyone know where I will get the just the worm drive that fits onto the later type Fowler 4P loco? It normally comes with the motor, but I have the motor but no worm drive. I am building this from a scrap model so I don't have an old motor to get one off. Someone on one of the other sites suggested that it is the same as an A1.

I bought a Peco one, but an ink rubber works just as well. I even glued one to a long stick for doing inside tunnels.

That is a bit worrying, I have got one of those. I fitted the TTS, did a couple of loops of my layout and then put it back in the box, I have been playing with my really old locos converting them to DCC lately. I thought you were going to say class 66, that is the one I had issues with. I better start doing some more testing on my Miles Beevor.

I have just had an issue with my tender powered Flying Scotsman, just couldn't figure why it kept slipping. Changed the traction tyres, still no difference. Anyway by changing tenders and locos about I found it was the loco, check that the wheels on the loco are buckled or slipping on the insulators in the centre of the wheels. That is what was wrong with mine. Because I have changed to 5 pole motor in the tender it has more power to push it along when something is wrong, with a 3 pole motor it would do exactly what yours is doing.

I surveyed EBay and found a supplier doing the Hornby 4 pin decoder quite cheap, so I "wimped" out and replaced the faulty four pin with a new four pin decoder. I am pleased to say it now works on DCC. Weird that the old one worked on DC but not DCC, but it looks like RAF96 is right, must have just been a bad batch.

A flickering LED has got to be the way to go, much more reliable and cheap. You need to feed it from a bridge rectifier, so it works in both directions.

I have been playing around with an old Seagull A4 and several A3s (all Ringfield) for the last couple of days converting them to DCC ready and adding 5 pole motors. Sarahagain is right perhaps the motor is not clipped in properly to the frame. The other thing I had issues with were the centre wheels of the motor (the axle between the two driving wheels) not lifting up properly. The other thing is the pin between loco and tender, sometimes there is a lip at the top, some pony trucks have the moulded bar at the top, some have a screw on drawbar at the bottom. It may be your father put the wrong pony truck on. You could try swapping pony trucks between the Scotsman and the Mallard and see if that cures it. The other thing I had issues with, was the wheels turned perfectly when I spun them, put when on the track the valve gear got stuck every so often. Make sure that there is a washer underneath the front bogie screw, that seems to make a real big difference, my A3 kept getting stuck until I put the washer in (it is 8 BA). It is not that strange a problem, I have spent hours trying to get my locos not to slide along when the tender pushes it.

Glad to hear you got it working. I found that with relay boards and points switching boards, they were cheaper than I could get the bits for. The way Hornby have done it on my controller, is to use I suspect a quad op amp, of which one is configured as a ramp and the rest are comparitors and buffers. Even with that you couldn't make it for less than £2.50. National semiconductors (I don't even know if they are still going) used to do applications in their data sheets, that is how I used to make most of my analogue circuits.

Great, thank you.

I was upgrading my Duke of Sutherland, ringfield based Patriot to DCC ready and adding an extra pickup to the loco so it picks up on both wheels (finding somethig to do during lockdown). No matter how I try, the loco slides. Anyway, eventually I took it apart to check for quartering and see if the valve gear was getting locked, when I noticed on one of the wheel spindles a bearing was missing. Does anyone know a part number for these? All the Service Sheets I read, indicate they come with the wheels.

Go on to EBay and get some from China. It is amazing the diversity of sizes and diameters they do. I try to source that sort of stuff from the UK, but you cannot get the range. Surprisingly the ones I have bought have been reasonable quality.

On the Zimo the blue wire is a flying lead, correct there is not a pin for it to go to, just like the extra function on 8 pin. If it doesn't have a flying lead there is a pad identified, it is the same one you wire one side of the "stay alive" to. A 6 pin in Zimo is the same as an 8 pin, it just doesn't have the extra two wires connected. On some of my locos I have 6 pin Zimos rewired to 8 pin, you cannot add "stay alive" to the Zimo 8 pin easily, but you can to the 6 pin (it appears it is a marketting decision), so I buy a 6 pin and do the rewiring. Interesting info about the decoder.