Reviving old Hornby locos (inc 2721 and class 91)

[Adrock]

Hi All,

 

Given the current lockdown, I’ve pulled out my old / original Hornby engines that I had as a kid for my boys to play with. They are:

 

1) a Caledonian pug

2) a 2721 pannier

3) a 1991 class 91

 

so far, I’ve got the pug working nicely after a strip down and a full clean. 
 

In terms of the pannier, again stripped and cleaned it runs well on its 2 (!) wheel pick ups as just a chassis. However, as soon as I put the body on it jerks all over the place. Wondering if this is because the weight pushes the sprung axle down, removing contact with the pick up, so it effectively is running on one pick up? Does this maybe indicate that the spring has gone? What Method has anyone used to :

 

1) remove the springs and replace with a bearing to create a rigid chassis?

2) added additional pickups?

3) has anyone changed the wheel sets to a non- traction tyred version? how do you even remove wheels from their axels?

 

Finally, the 91 seems completely dead. Any ideas on where to start with this one?

 

Thanks all. 

[andyman7]

Re the class 91 check the roof switch is set for track pickup.......! Otherwise, for this (or indeed any Ringfield fitted loco) if it is dead on the track my first port of call will be to try applying power directly to the brush retaining strips. If the motor works then the fault will be somewhere between there and the wheels; if not, then you know the problem is right there in the armature. First thing to check is that both brushes and springs are there and bearing down on the commutator - I've very often found that a dead motor is simply because a brush spring has gone astray. If the motor runs and the problem is between there and the wheels you need to check all the tag joints, that wheels are clean (and installed the right way round); basically keep going until you find out where the power is not getting through. Whilst you are at it, unless everything is clean and in good order a through clean up and relubrication  always helps.

Edited April 20, 2020 by andyman7

[Pete the Elaner]

1 hour ago, Adrock said:

 

Finally, the 91 seems completely dead. Any ideas on where to start with this one?

 

 

Remove pickups from the list of possible faults by applying a voltage directly to the brush retaining arms.

[Adrock]

Thanks both - this is really helpful as a start. How do the pickups on the 91 work? Is the inner section of the bogie effectively “live” and it collects from the axle? I can’t see any traditional wiper pickups. 

[RAF96]

One side of the 91s wheels is live to the axle and thus to the motor housing, thence to one motor brush. The dummy bogey picks up the same way but with the axle reversed, then via the roof switch to the other motor brush. The wire connections are simple push on Lucar type connectors and can drop off. 

 

I have improved the pickups on a 90 by using dummy bogie wheels which have gears on the motor bogie. This gets rid of the traction tyres. You can also fit the later four wheel pickups to the dummy bogie ‘chassis’ block. See here for how I did the 90.

http://www.halton96th.org.uk/article6.html

 

[Ruffnut Thorston]

Older Ringfield motor Diesel and Electric locos have the pick up split between the motor bogie and the trailing bogie.

 

The motor bogie picks up from the non traction tyred wheels, through the axles, the motor block, and thence to the left hand, looking at the motor from the faceplate, brush retaining strip.

 

The connexion between the block and the brush strip can be via a protuding part of the block bearing on the rear of the brush retaining strip, a bridge wire between the block and the brush retaining strip, or if the brush retaining strips are screwed in place, by the left hand screw tapping into the motor block.

 

The trailing bogie pick up should be via the non insulated wheels, which should be on the same side, or rail, as the traction tyred wheels.

 

This bogie has a wire that feeds to the right hand brush.

 

On electric locos with operating pantographs, via a selection switch...

 

The 2721 wheels are a push fit onto the axles...

 

 

Edited April 21, 2020 by Sarahagain
typing while another posted...

[The Johnster]

My 2721 has a sprung rear axle which is a rather crude piece of kit, two springs mounted in holes rebated into the bottom of the chassis block and bearing directly onto the axle.  My s/h loco was bought as seen as a poor runner (3 legged dog with 3 different legs came to mind) and this was due to several factors.  Firstly, it had been overlubricated and gunged up, secondly the traction tyre was disrupting pick up (they always do; I hate them).  A deep clean and relubing, along with the removal of the tyre, solved those problems and improved running very significantly, but she still wasn't smooth and a third problem was clearly in play.  I suspected the sprung rear axles and had noted when I stripped her down for a deep clean that they bore directly on to the axle, 

 

Assuming that there was some sort of bearing plate that was missing, I downloaded the service sheet from Hornby's website, which showed that all was present and correct and the model is designed to have these two springs bearing directly on to the axle, which had scratch marks corresponding with the position of the springs.  The sheet suggest that you can adjust the spring pressure by strengthening (stretching) or weakening (trimming) the springs.  As things were, the springs were too powerful, lifting the back of the loco.  

 

I decided not to trim the springs. a sure recipe for one of them pinging off into orbit, but instead removed the plastic coal from the bunker, something I was going to do anyway with other measures to work up the model into something slightly less unacceptable (along with new buffers, chimney, dome, safety valve cover, crew, planked cab floor, cab window glazing, and a repaint; the tyre grooved wheel was replaced with one from the scrap box).  The bunker was then ballasted with 'Liquid Lead' and a layer of coal placed on top of it.  The loco now sat properly on the rear axle, and her slow running improved further.  She still wasn't a smooth starter and stopper, though, and I gave some attention to keeper plate screws and gear meshing, both of which further improved running, but I'd seen generic Triang Hornby Jinty chassis of this sort perform better and knew she had a smooth runner trapped inside her.  The final act was to smooth down the rough ends of the springs with a piece of emery, and smear a very small amount of graphite grease on them.  

 

She is now a very good performer indeed, smooth, slow, and powerful, but does seem to attract crud on her wheels and pickup surfaces more than my most of my other locos; a Lima 117 converted to 116 back in the day that gets an occasional outing as an excursion is as bad.  So, your 2721 can be made to run properly, but it is a bit of faff and takes time and a process of elimination.  My advice is to get rid of the traction tyre and replace the wheel if you can, and check the spring pressure on the rear axle.   I have squeezed ballast in the form of blutac everywhere I can on this loco, as is my usual practice, and this will improve haulage while at the same time bearing pressure down on the pickup wheels.  I have not found it necessary to provide pick up to the centre axle, but there is no harm in doing so if you wish to.  The traction tyre on mine was lifting the opposite wheel off the railhead, so pickup relied on the front wheelset alone, meaning the loco could not traverse a dead frog.

[Adrock]

Thanks for all of the comments - these have been really helpful. 
 

On my 2721, I think my springs on the rear axle are shot, as rather than being too powerful, as soon as the body goes on the body sinks the axle right down to the bottom. I think I will remove them and somehow convert to a normal bearing. Where can you source replacement wheels from to replace the central traction tyre by the way? I don’t really need too much pulling power - it’s just for the kids to whizz around their own track with!

 

On the 91, I will try and bypass the pickups to check the motor. I have noticed quite a bit of black gunk in the middle so may need to strip it down at some point. 

[Ruffnut Thorston]

You may find that replacing the chassis of the 2721 with a current Railroad 0-6-0 chassis would be the easiest option.

 

The "Jinty", Railroad 08 diesel shunter, the LNER J83 (I think) and the 2721 all share the same basic chassis. The 08 has an adaptor bracket, but the chassis is the same.

 

Current Railroad locos have bearings, not springs, on the rear axle. No traction tyres. Flanged centre driving wheels.

 

Some also have a socket for a Hornby 4-pin DCC decoder, DCC Ready...

 

You could sell on the old chassis.

 

Possibly with the body from the doner loco for the new chassis?

 

I think that you may find wheels, etc from spares places like Lendons of Cardiff, Peter's Spares, etc.

 

The hardest part would seem to be fitting some kind of bearing for the rear axle.

 

Maybe some brass tube araldited into position?

 

This would mean fitting the rear wheels onto their axle in the chassis, like the old Tri-ang cast chassis blocks...

 

It can certainly be done though...

 

 

 

Edited April 21, 2020 by Sarahagain
more added

[Adrock]

16 hours ago, Sarahagain said:

You may find that replacing the chassis of the 2721 with a current Railroad 0-6-0 chassis would be the easiest option.

 

The "Jinty", Railroad 08 diesel shunter, the LNER J83 (I think) and the 2721 all share the same basic chassis. The 08 has an adaptor bracket, but the chassis is the same.

 

Current Railroad locos have bearings, not springs, on the rear axle. No traction tyres. Flanged centre driving wheels.

 

Some also have a socket for a Hornby 4-pin DCC decoder, DCC Ready...

 

You could sell on the old chassis.

 

Possibly with the body from the doner loco for the new chassis?

 

I think that you may find wheels, etc from spares places like Lendons of Cardiff, Peter's Spares, etc.

 

The hardest part would seem to be fitting some kind of bearing for the rear axle.

 

Maybe some brass tube araldited into position?

 

This would mean fitting the rear wheels onto their axle in the chassis, like the old Tri-ang cast chassis blocks...

 

It can certainly be done though...

 

 

 

I don’t disagree with you and this would normally be the approach I would follow. Part of me really wants to fix it myself though, especially as the cost of second hand panniers etc with the latest chassis are unbelievable - one went for 49 on eBay last week! 
 

On my version, where does the other brush connect to by the way? Is it a live chassis on the axle? As pickup wipers are only on one side. 

[Ruffnut Thorston]

I know what you mean, prices can be crazy..

 

On the subject of weight, some at least of the locos have a cylindrical metal weight black takked inside the bunker.

 

Some also have a similar weight inside the smokebox.

 

The versions of the 0-6-0 chassis with wipers only on one side do return through the chassis and axles.

 

Service Sheet 201 December 1997...

 

http://www.hornbyguide.com/item_details.asp?itemid=1390

 

 

Other versions have a second set of wipers...

 

 

 

 

 

 

Edited April 22, 2020 by Sarahagain
more added

[Adrock]

Latest update on this, with the 2721 I packed out the rear compensation springs with plastic to “simulate” a rigid chassis. I then tested the chassis and it displayed the same jumpy characteristics as when the body had been put on previously. The wiper was sitting a bit higher up the wheel, so am convinced poor pickup is the major root cause. 
 

I reverted that one and took off the traction tyres. Having replaced the body, I’ve found it’s now running really smoothly and it can creep at really slow speeds just like when the body was off. I think the pick up wiper touches the top of the middle wheel, so maybe the pickup capacity has been improved by removing the traction tyre. There’s a bit of a wobble when running but it works now, which is all I needed it to do. Maybe in the future I’ll put a proper set of picks up on all three wheels on each side.
 

Still have the 91 to strip down - that’s the job for this weekend. 

[Adrock]

I managed to strip down the motor bogie and get this working. It’s making a bit of squeal at certain speeds - not sure what’s causing, could be the gears need a light oiling on the spindles? 
 

Also, does anyone know what the blue transitior is joining the two brushes? Can I remove this?

[Pete the Elaner]

Squealing can be caused by the main bearing running dry. A tiny drop of oil in the main bearing may shut it up (in your photo between the copper brush retaining tabs).

The blue component is a capacitor for interference suppression. These motors used to interfere with radio & TV signals. The capacitor is there to eliminate this. The motor will run fine without it but I am not sure how digital TV & DAB radio are affected.

DCC decoders prefer to not have the capacitor there. They are designed to monitor the motor without a capacitor's interference, so many remove this when fitting a decoder.

[Ruffnut Thorston]

There is a brass bearing behind the main spur gear on the other side of the motor.

 

This usually likes a bit of oil.

 

The bearing between the brush retainers is just a hole in the plastic faceplate.

 

Hornby Railways used to recommend using petroleum jelly to lubricate this bearing, as if  too much oil is used, it will drop onto the commutator of the armature...not a good idea. It makes the carbon brushes go soft and squidgy.

 

The driving gears are plastic on stub "axles", cast spigots, on the motor casting.

 

A drop of oil won't hurt.

 

Then there are the axles, inside the brass tube bushes...they like a bit of oil too.

[Adrock]

On 28/04/2020 at 21:49, Sarahagain said:

There is a brass bearing behind the main spur gear on the other side of the motor.

 

This usually likes a bit of oil.

 

The bearing between the brush retainers is just a hole in the plastic faceplate.

 

Hornby Railways used to recommend using petroleum jelly to lubricate this bearing, as if  too much oil is used, it will drop onto the commutator of the armature...not a good idea. It makes the carbon brushes go soft and squidgy.

 

The driving gears are plastic on stub "axles", cast spigots, on the motor casting.

 

A drop of oil won't hurt.

 

Then there are the axles, inside the brass tube bushes...they like a bit of oil too.

Thanks. I have oiled the brass gear and the plastic gears. I have also replaced the springs and brushes but is still making a horrendous noise! Any further ideas?

 

many thanks. 

[deek]

Hi Folks,

I was very pleased to find this thread on 0-6-0 locos, as I have an old Hornby 08 shunter (not dcc ready!) 

I want to try fitting a decoder in this, but looking at the workings (as per drawings on this thread) there is not the customary pair of wires between pickups and motor to interrupt with a decoder.

Can anyone give me any pointers as how to fit a basic 4 wire decoder to this loco?

Many Thanks, Derek.  

[Adrock]

On 02/01/2022 at 10:38, deek said:

Hi Folks,

I was very pleased to find this thread on 0-6-0 locos, as I have an old Hornby 08 shunter (not dcc ready!) 

I want to try fitting a decoder in this, but looking at the workings (as per drawings on this thread) there is not the customary pair of wires between pickups and motor to interrupt with a decoder.

Can anyone give me any pointers as how to fit a basic 4 wire decoder to this loco?

Many Thanks, Derek.  

I know this is an old post / thread but thought I would respond to record my findings anyway in case they’re remotely helpful in the future! I did quite a bit of research into the 0-6-0 chassis, and I believe there are 3 different “modern” versions  ie since the mid-90s:

 

1. Version with just 2 pickups, flange less traction tyre on the centre wheel set, sprung rear axle and shiny wheels and motion. In this scenario, this is as described in one of the posts above where the chassis is live for the return feed. This has 4 screws when viewed from underneath 

 

2. Modified version with addition of two more pickups on the other side, removing the need for the chassis to be live. Wheels and motion now blackened, but rear axle spring still retained. I believe this change was made in the very late 90s and is referenced in the service sheets at the time (201 & 201B). This version has 5 screws when viewed from underneath.

 

3. further modification removing the spring rear axle and replacing it with a fixed arrangement. Definitely no traction tyres and centre wheel set is flanged. I don’t know whether the version at point 2 above had these two features or not. 
 

I have actually just bought a loco with a chassis of the version at point 3 to replace one from point 1 for my 2721. The replacement is a 2011 model and comes in a Railroad box, I’m thinking it will be a superior runner and will be easier to convert to DCC.
 

incidentally, I wonder if these final changes were made as part of the process of Hornby offering this chassis as DCC fitted in some of its starter sets?

 

[The Johnster]

I did quite a bit of work on my 2721, replacing chimney, dome, safety valve bonnet, real coal, even a drophead coupe deployed canvas weather sheet.  Couldn't get any Hornby chassis to run the way I wanted, even 'type 3', and eventually went down the Bachmann pannier chassis road, despite the wobbly alignment with the splashers and the wrong coupling rods for my prototype, which had parallel fluted.  In the end I found I couldn't live with the oversized bunker and wrong coupling rods (paradoxically the splasher alignment was not intrusively noticeable except in a dead side-on view), and gave up; the model is now withdrawn from service and the Bachmann chassis back under it's donor 57xx.

 

New tooling 2721 Mr Kohler, please, and not in TT, that's no use to me!

[tomparryharry]

I too, have a 2721 pannier.  The Hornby chassis has been uprated with Romfords, and new rods. It runs ok, but only because the pickups are a bit of a problem for me. Gibsons sell the correct rods, and I've used 1/8" bushes, also from Gibsons/Markits.

 

It's out of my technology zone, but 3D printing might afford a decent upgrade to the humble pannier, especially around the footplate/lower boiler area. 

 

It's strange, but I've got a funny feeling about a tender-driven Dean Single, even though they didn't work into my area....

 

Still, let's have an orange Flying Scotsman; we haven't had one of those yet....