[Michael Mackenzie]

A couple of days ago my "Kingfisher" A4 Pacific (from the Rare Bird set) developed an odd fault whereby it would periodically speed up and slow down. At first I thought perhaps the track or the pick-ups were dirty, so I gave both a thorough clean, but the problem persisted. I tried it with two different controllers and on two different loops of track. (My other locomotives behave properly on the same track.) I then tried running the locomotive on the spot (by placing one of those Hornby plastic buffers on the track), and this is the result:

Just to clarify, once I turn on the power at the start, I don't touch the controller until I switch it off at the end of the video - the loco is speeding up and slowing down of its own accord.

Does anyone have any suggestions? Duff motor? Something else?

Many thanks,

Michael

 

[Big Dave]

Hi Michael are you running on DC or DCC if its DCC then it will be the decoder. but let ouse know what your running on. vids are not working.
Dave

 

[Michael Mackenzie]

Hi Dave,

Sorry, should have said - it's DC. And the vid should be accessible now.

Michael

 

[Brian Considine]

I would say its the motor (however, last time I said that to someone on MRF it was'nt !).

Try running the locomotive "on the bench" with the controller wires connected directly to the motor - if it shows the same symptoms suspect the motor.

 

[Michael Mackenzie]

Brian,

Must admit that sounds a little beyond my expertise - I've only recently got back into railways after a 15-year hiatus and am a little wary about dismantling a model as intricate as a "super-detail" A4, let alone connecting the wires to the motor directly. Reckon I'm going to have to hop on the bus and take it to my nearest (and I do mean relatively speaking!) model shop - annoying as I was in there earlier today dropping off another sickly loco and picking up a new controller.

Thanks for the advice though.

Michael

 

[kristopher1805]

OK a few things about this I do not like much

1. There is a knock somewhere sounds like a big end but is internal somewhere

2. Both the drive axle and the rear axle look to be running out of true as the wheels are back and forth

This may mean that the mechanism inside is getting tighter when it slows or slacker when it speeds up.

Now this is also affected by other issues and sometimes these are not obvious such as gear meshing, how it behaves under load can affect the loco too, whether it is getting hot or not. So give it a lubrication from a pencil dropper, clean the drive wheels then give it a good thrash, nothing like a very long hard run to bed it down a bit, this is sometimes all it needs, work it backwards and forwards as well, see how you get on.

 

[Michael Mackenzie]

Hey Kristopher,

Thanks for the advice. I'll give lubricating a shot and report back.

 

[Michael Mackenzie]

OK, so I've lubricated the wheel axles and linkage and sent it off for a long, taxing run. The speed was pretty inconsistent for the first ten minutes or so, but since then it's been running at a fairly consistent clip for the last half hour or thereabouts. I'm going to give it a bit longer before calling it a night, and we'll see how it runs tomorrow after it's had a while to cool down etc.

Cheers guys.

 

[Michael Mackenzie]

Hmm, well, after a good night's sleep, it's started doing the speeding up/slowing down thing again. Time to get someone with more expertise than me to take a look at it, I think.

 

[nick lamkin]

Just a thought - Motors tend to run hot if all is not well. Does the motor seem to be overheating?

 

[Michael Mackenzie]

Nick:

The loco certainly doesn't feel unusually warm or anything, and the fact that it settled down to a consistent speed last night after heavy use would seem to suggest that the issue isn't the motor being overly taxed.

Reckon I'll get on to Model Railways Direct (who I bought it from) and see if there's any chance of them doing a swap or a repair.

 

[nick lamkin]

If the motor is not getting warm - its unlikely to be the cause. Also unlikely to be gears jamming as this would cause the motor to get hot was well. Poor or dirty pickups or even a dry joint in the wiring may the answer.

Nick

 

[Michael Mackenzie]

Well, either way, I'm going to give Hornby a ring tomorrow and see if they can do anything with it. Model Railways Direct have long since sold all their Rare Bird sets, so the best they could offer me was a refund, which I understandably didn't want. My collection wouldn't be complete without an A4 in Express Blue.

Thanks again for all the suggestions, folks.

 

[Michael Mackenzie]

Apologies for resurrecting an old thread, but I thought I ought to let you know the state of play. I received the loco back from Hornby today along with a letter stating that they had tested it under normal running conditions and found no fault. Upon opening the box I was dismayed to find that not only was the footplate loose but the two cab doors had been broken off and were nowhere to be found.

Things got even worse when I put the loco on the track. It seems to run forwards perfectly well, but when putting it into reverse the motor makes a loud grinding sound and it barely moves at all, even at full power. Talk about going from bad to worse!

Needless to say I'm not impressed and will be getting back in touch with Hornby post haste.

Michael

 

[Wales]

Hmm, well, after a good night's sleep, it's started doing the speeding up/slowing down thing again. Time to get someone with more expertise than me to take a look at it, I think.

TTo clean out the dust & rubbish, I always (this sounds daft). Hold a can of lighter gas’s to the underside &press so that the gas goes into all the nooks &crannies. Do this on an old cloth &you will be amazed at lol of the junk that comes out . Then recoil.
Thanks Dave Gould, Saundersfoot, South Wales..