Bachmann A1 mechanism and running improvements

[AHW]

Apologies if this has been covered elsewhere - I did search the site first but couldn't spot anything relevant.

 

I own four Bachmann A1's - one brand new which seems fine on running in, and three second hand. I don't know much about the service record on those three and one at least seems a little rough - noisy - jerky and very wobbly.

 

Whilst I'm good with my hands - I actually have very little experience of working on model locomotive mechanisms. Before I begin 'improving things' can anybody make any useful suggestions on this topic.

 

Should I just swap out the motor/gear box for newer or can they be improved?

 

Are the valve gears and drive rods likely to be an issue - can they be fettled to improve running?

 

(Lubrication is an an obvious issue already covered)

 

Many thanks in advance for any suggestions.

[31A]

A thing to check with the Bachmann A1 (as with a lot of Bachmann engines of this generation) is the operation of the sprung driving wheel axle; in this case it is the leading axle. Whilst a very good idea in terms of improving current collection and I wish their newer locos also had them, they can become jammed when the factory - applied 'white grease' solidifies after a number of years.  The A1 as a model has been around for quite a while now, so if any of these are from early batches that could well be the case.

 

If the sprung axle plunger can't move up and down freely it can cause intermittent wheel / rail electrical contact, and could also be the cause of the jerky and wobbly running.

 

You need to release the 'keeper plate' plastic moulding off the bottom of the loco mechanism by removing the screws you can see along the bottom of the loco.  The keeper plate will then lift off bringing the front bogie with it, but remains attached by the pick up wires at the cab end.  You don't need to detach these.  Then lift the driving wheels out and you'll see the sprung plunger above the leading axle.  If necessary clean all the white grease from this, re-lubricate it with suitable thin oil, and re-assemble.  Be careful not to lose the spring from the plunger!

 

If your models have the Service Sheet with them you should be able to see on this which screws need to be removed.

 

https://www.lendonsmodelshop.co.uk/pdf/Bachmann OO Service Sheets/Class A1.pdf

 

While you're at it (and depending how much you want to dismantle) you could strip the rest of the white grease from around the gears etc., and re-lubricate them as well with oil, together with the axle bearings and coupling rods, etc.  Also when re-attaching the keeper plate, make sure all the pick up wipers are pressing against the backs of the wheel tyres at all times, when the wheels move from side to side.  If not, it is easier to put a slight bend into them to increase the pressure before you re-attach the keeper plate.

 

With mine, I found the 'fall plate' (rearward extension of the cab floor to the tender) was resting on the front of the tender, causing the rear driving wheels to be lifted from the rails at slight undulations of the track.  This piece is metal, and it's quite easy to put a slight upward bend into it so that it is clear of the front of the tender and no longer causes the loco wheels to be lifted.

 

[AHW]

21 hours ago, 313201 said:

For the Bachmann A1 the rods only really need lubrication now and again so no worries there.

 

As far as the internal workings are concerned there can be several causes of noise or jerky running, any of which could be the following :

 

1, The motor may require lubrication of the bearings.  Caution, do not lubricate the motor at the wired end, this will cause the brushes to get gunked up very quickly and will smoke your motor, therefore, only lubricate at the worm gear end.

 

2, The gear cogs may be dry which causes a grinding or cogging sound, again some lubrication with oil or grease suitable for model locomotive gears will help a lot.

 

3, The pickups may not be making proper contact with the driving wheels, some minor adjustments to these may be required aswell as cleaning the back of the wheels.

 

4, You haven't mentioned whether your layout is standard dc or dcc ( digital command control ), you will see a socket into which is fitted an 8 pin plug if you run on dc or a decoder chip with a few multicoloured wires plugged into it.  Whichever is fitted into your locos, a light press on the plug will ensure that there is a good connection as sometimes the plugs are not always properly fitted which causes a bad connection.  Also if you run standard dc wiring and do not want to use digital command control ( dcc ) then those 8 pin sockets can be completely removed and the motor wired directly to the pickups, if you do this, cut the wires as close to the socket as possible as this will give you plenty of wire to work with and if you get stuck wondering which way to connect the pickup wires to the wires from the motor, strip the wires, put the loco on the track, set the speed control to forwards and touch the pickup wires to the motor wires and it should go fowards.

 

If the loco goes backwards then its simply a case of swapping the pickup wires over and connecting them to the motor wires and once tested and the loco thengoes forwards with the controller set forwards its job done.  You can use heat shrink or insulation tape to cover the soldered connections of the wires but if using heat shrink this must be placed on the wires before soldering them.

 

I have the Bachmann Tornado locomotive and as I do not run dcc I completely removed the decoder socket and wired the motor direct to the pickups in the procedure described above but went further with my loco and even though Bachmann steam locomotives do not need tender pickups, I made and fitted pickups for Tornado's tender which once they were connected to the motor improved the running which is now much smoother.

 

When I compare my Tornado locomotive to another Bachmann A1 I own which is numbered and named as 60153 Flamboyant, this loco is much different to Tornado as I coupled it to a Hornby scotsman tender drive converted with a cd motor and it goes like a bolt of lightning around my layout so it felt like I had to learn to drive it, luckily that didn't take too long to do.

 

My apologies for the digression and I hope theabove tips help, however, if not then please do ask any questions you may have. 

This is really helpful - thank you for taking the trouble to respond.

[AHW]

21 hours ago, 31A said:

A thing to check with the Bachmann A1 (as with a lot of Bachmann engines of this generation) is the operation of the sprung driving wheel axle; in this case it is the leading axle. Whilst a very good idea in terms of improving current collection and I wish their newer locos also had them, they can become jammed when the factory - applied 'white grease' solidifies after a number of years.  The A1 as a model has been around for quite a while now, so if any of these are from early batches that could well be the case.

 

If the sprung axle plunger can't move up and down freely it can cause intermittent wheel / rail electrical contact, and could also be the cause of the jerky and wobbly running.

 

You need to release the 'keeper plate' plastic moulding off the bottom of the loco mechanism by removing the screws you can see along the bottom of the loco.  The keeper plate will then lift off bringing the front bogie with it, but remains attached by the pick up wires at the cab end.  You don't need to detach these.  Then lift the driving wheels out and you'll see the sprung plunger above the leading axle.  If necessary clean all the white grease from this, re-lubricate it with suitable thin oil, and re-assemble.  Be careful not to lose the spring from the plunger!

 

If your models have the Service Sheet with them you should be able to see on this which screws need to be removed.

 

https://www.lendonsmodelshop.co.uk/pdf/Bachmann OO Service Sheets/Class A1.pdf

 

While you're at it (and depending how much you want to dismantle) you could strip the rest of the white grease from around the gears etc., and re-lubricate them as well with oil, together with the axle bearings and coupling rods, etc.  Also when re-attaching the keeper plate, make sure all the pick up wipers are pressing against the backs of the wheel tyres at all times, when the wheels move from side to side.  If not, it is easier to put a slight bend into them to increase the pressure before you re-attach the keeper plate.

 

With mine, I found the 'fall plate' (rearward extension of the cab floor to the tender) was resting on the front of the tender, causing the rear driving wheels to be lifted from the rails at slight undulations of the track.  This piece is metal, and it's quite easy to put a slight upward bend into it so that it is clear of the front of the tender and no longer causes the loco wheels to be lifted.

 

Many thanks for this - really helpful. I was thinking of using some Trix grease on the gears - do you prefer oil....?

[31A]

27 minutes ago, AHW said:

Many thanks for this - really helpful. I was thinking of using some Trix grease on the gears - do you prefer oil....?

 

I do use oil, but that's mainly because I've always used it and haven't got any grease!  There are several suitable kinds of grease, I should think anything sold by Trix would be fine, and would probably last longer between applications.

 

[peterfgf]

For my pennyworth, I think oil might be better.  You are trying to lubricate the gears and getting lubricant  to keep the teeth separate whilst rotating and hence reduce wear and friction is the aim.  I suspect grease is a bit too stiff/viscous and only adds to the drag on the rotating parts.  I had a Heljan Class 17 where the gear towers with stuffed full of grease and which ran much better after clearing it all out.

Peterfgf

[AHW]

Well a strip down of the offending engine did not uncover much. There wasn't much of the white grease in the lead driving wheel plunger but some around the gear box. I've cleaned out and oiled as per directions. However this hasn't made much difference. I'm not that impressed with the mechanism to be honest and I'm planning to investigate other ways of improvement - I may look into swapping out the complete drive train. Thanks for the helpful comments - much appreciated.

[Brit70053]

I haven't seen any mention of the motor problem which afflicted some first release models,' Aberdonian' and I think' North Eastern'. If I recall, some of the motors, including the one fitted to my 'Aberdonian' were incorrectly wound and this resulted in both an inability to pull any worthwhile load and in overheating to such a degree that body mouldings were in danger of melting in some extreme examples. The problem was very random, my friend bought an identical model to mine at the same time in the same shop and had no problem whatever.

Bachmann did investigate and returned some models (mine included) to China for attention, they were, after a considerable time, returned with new motors (and possibly some change to the drive gear chain ?).

              If your poorly performing model is one of these early issues, it would indeed be worthwhile looking at replacing the  motor if something suitable can be sourced. Bachmann's spares dept. may be able to help. Can you remove the motor and  test it in isolation, this may give you anindication if that is where the problem lies.

             Good luck,

 

                                 John