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Poorly performing Farish Poole-built 5 pole motors

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I have a number of old locos that run poorly, if at all.  At full track voltage, they barely move.  Attaching power to the chassis and centre-screw makes little difference.

 

What is the preferred maintenance - replace brushes and springs, replace whole motor(s), something else?

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May need to change the topic title :)

 

Pulled out the wheels so that only the motor is in the chassis - it spins freely to whatever speed I want.  So, either there is a problem with the gear/worm-wheel link (seems OK), or the motor fails with any load.

 

Would appreciate any thoughts...

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Do the wheels move freely without the motor in the chassis? 

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Which models? Steam? Diesel?

 

Does the loco move a little bit before stopping? If the motor runs without the wheel set fitted then you've probably got split gears:

http://www.ngaugesociety.com/index.php?page=split-gears

 

You can get replacement gears or axles from the N Gauge Society or BR Lines.

 

With the motor removed (i.e. the worm gear) try to rotate the wheels by hand. If they lock up then you've likely got a split gear. If they do rotate but are very stiff then they could just need stripping down, cleaning and then re-assembling with some plastic friendly grease/oil.

 

 

Happy modelling.

 

Steven B.

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Sometimes also on them the gears go loose on shafts which on the wheels will stop them griping and produce a lot of wheelslip

the only cure is to replace usually the drive wheels on the diesels and on the steam

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Thanks for all the replies...all steam, a 3F Jinty, a Pannier Tank, a Hall Class and a Merchant Class.  All exhibit the same characteristics on track - full voltage but no or slow crawl movement only, so slow it takes about 15 seconds to travel 1"

 

Have only stripped the Jinty and Pannier, removed the wheels/axles from the chassis and applied power - the motor screams along.  Washed main gear axle/wheel in metho to remove visible gunk, reset it an applied a pinhead of lube oil.  Apply power while the chassis is detached from the body, and upside down and....again it crawls.  Motor heats up as if it is being restricted from turning.  So it is either the gear mechanism that is somehow frozen, even after cleaning and reseating, or the motor doesn't want to work under load...or?

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The drivetrain must be tight if the motors run otherwise.

Don't run them for any time if they are getting hot - you'll get much more damage inflicted and risk burn out.

 

Have you cleaned and lubricated the axle slots? Also, try loosening the keeper plate screws just a fraction in case the plate is pinching the axles (they should slide freely along their length when in the chassis. Check also the pickups are not too tight against the wheels (particularly if these are early 3 pole models that have quite stiff pickup material).

 

On early Farish the magnets can weaken with time - in particular the silver motor magnets (later ones are dark grey). If yours are silver I'd recommend changing them out - BR Lines sell new magnets for a few £. These generally make a huge difference to the early models.

 

HTH,

Alan

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Hi,

Difficult to diagnose remotely, but a couple of mechanical things - maybe the worm is riding up the worm wheel, or possibly not aligned correctly. Also, could be the end thrust on the worm moving the armature/shaft, causing it to jam. With the motor removed, try pressing on the end of the shaft when running (with something hard, flat edge of a knife blade or similar, not your finger). (I'm assuming that the wheels rotate freely without the motor drive connected).

 

hth

 

Best wishes,

 

Ray. 

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Dr Al

 

Pulled the Jinty apart again...I think that it has a dark grey magnet, it is certainly not light coloured.  With the axles removed, the armature and worm move freely.  With the axles in place and whether the base plate is screwed in place or not, the axles will not move; I expect that this is correct?

 

Contacts are not pressing to hard, have cleaned and adjusted them and cleaned the back of the wheels too!  Placing the chassis onto a rolling road, at full power, the motor just turns very slowly.  Would be great if it was the minimum speed, ideal for shunting....

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Dr Al

 

Pulled the Jinty apart again...I think that it has a dark grey magnet, it is certainly not light coloured.  With the axles removed, the armature and worm move freely.  With the axles in place and whether the base plate is screwed in place or not, the axles will not move; I expect that this is correct?

 

Contacts are not pressing to hard, have cleaned and adjusted them and cleaned the back of the wheels too!  Placing the chassis onto a rolling road, at full power, the motor just turns very slowly.  Would be great if it was the minimum speed, ideal for shunting....

 

The worm will stop the wheels turning by hand when reassembled, yes, though the axles should be relatively free sliding in their slots along their length.

 

Beyond this, without some pictures or seeing the model in the flesh, it's difficult to know what else to immediately suggest, other than:

 

- lightly lubricate the drive gear on the central axle

- lightly lubricate the motor bearings (DON'T get oil on the motor commutator though!!!)

- clean the commutator

- if this is a newer style Jinty (as opposed the GP tank painted as a JInty) with black 16 tooth gear on central axle, this gear could have split (they are prone to it). It can be replaced if this is the case.

Cheers,

Alan

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Well, I would like to attach photos but apparently I can only do it via URL rather than uploading images...and I don't have a photo sharing site, so that's handy...

 

I'm afraid I have mislead you, it isn't a Jinty but a Pannier Tank, http://www.ehattons.com/9271/Graham_Farish_371_953_Class_94xx_0_6_0_Pannier_tank_9409_in_GWR_green/StockDetail.aspx

 

The central axle has a black plastic gear on it - there are more than 16 teeth, so probably 24?  The motor is 5 pole and it has a metal body and is GWR green.  Applying moderate force to the black plastic gear doesn't make it move on the axle at all, so I suspect that means it isn't split/cracked.  Can't see a crack using a magnifying glass.

 

Have tried:

  1. lightly lubricate the drive gear on the central axle
  2. lightly lubricate the motor bearings
  3. clean the commutator

I would have thought that 2 & 3 would mean the motor wouldn't spin well at all, even when disconnected from the axle?  It spins fast and slow without the axle engaged.

 

Thanks for your help.  If I can get to the bottom of this, then that may solve the others as they all exhibit exactly the same problems...

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Ok, it definitely won't be a split gear then - the 25 toothers rarely split.

 

Difficult to know what else to now suggest - do you have an ammeter that you can see what current the motor is drawing when spinning freely? Sometimes it's easy to think it's free but actually it isn't - your hands can exert a huge force or torque compared to the motor's output. Something may well still be stiff.

 

Cheers,
Alan

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Wow!! 1.7A, that can't be good :(

OK Gremlin,

 

You are correct - 1.7a is not good and indicates there is at least a partial short either in the armature wiring or between the poles of the comutator.

 

From what you have described and the various things you have already tried - you will not be able to save this motor or any other which is taking such a high current.

 

Your best bet is to search on EBAY or the various spares suppliers for replacement armatures.

 

Thanks

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Hi Scottish Modeller

 

Are all the locos the same armatures, or, how do I find out which armatures they use?

 

Cheers

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Hi Scottish Modeller

 

Are all the locos the same armatures, or, how do I find out which armatures they use?

 

Cheers

HI Gremlin,

 

Not all the armatures are the same.

 

Mostly they are different for each model in the range - there are some models that have what appears to be the same armature but with small differences that are enough to prevent them working. 

 

From what you have described you have a Graham Farish, Poole made, GWR Pannier Tank 9400 class. 

 

This is one which does share armatures though, the same armature - The Type 1, is used in the General Purpose tank engines and Class 08 Shunter.

 

If you use the contact details on this web site

 

http://www.brlines.com/

 

I'm sure Bob will sort you out.

 

Failing that, try this link and do the same

 

http://www.petersspares.com/spares-graham-farish-spares.irc?id=9022839&pg=3

 

Any other questions - post them up here!

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Thanks for that - the link http://www.petersspa...id=9022839&pg=3 shows type 1 armatures for "steam" - I wonder if that infers ALL steam...the other locos playing up (all Poole 5 pole) are a Hall Class, a Merchant Class and a Prairie...all steam...

 

I will be bringing them all to the UK next week for some R&R&R (the latter R meaning repair)

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Thanks for that - the link http://www.petersspa...id=9022839&pg=3 shows type 1 armatures for "steam" - I wonder if that infers ALL steam...the other locos playing up (all Poole 5 pole) are a Hall Class, a Merchant Class and a Prairie...all steam...

 

I will be bringing them all to the UK next week for some R&R&R (the latter R meaning repair)

Hi Gremlin,

 

As I said in my post - it appears that the Type 1 armature fits all but my experience has confirmed that is not always the case. This can be caused by either or both the armature winding or gear not being fitted correctly and causing a mismatch with the motor housing and pole plates.

 

One of the things you will find over time will be that when they run hot - it's nearly always a case of needing a new armature.

 

On occasions you will find that the heat distorts the white/clear/grey nylon bushes that the armature runs in and that a temporary repair is possible by reaming these out slightly so that the armature can run freely again.

 

Over time this becomes a further problem and is not repairable - you then need not only the new armature but some new bushes as well.

 

Thanks

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Thanks for all the help, unexpected fun times when I arrive next week, must try to find some track in London to test the locos if I can do the surgery there.... :)

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1.7A? Are you sure that's not 170mA (ok)? If it was drawing 1.7A it would be burnt out by now - they cook at about 0.5A+ in my experience.

 

Cheers,
Alan

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Well, it was set to a 10A range and showed 1.7A....I have measured over 2A being drawn when 3 locos are running, so they must be capable of drawing more than .5A and surviving, possibly badly :)

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Something is definitely wrong there, either with the control, current measurement, and/or locos themselves. It's difficult to know what else to suggest now without seeing the offenders in question!

 

Certainly locos pulling that current (which I struggle to believe is right) are likely to be doing irrepairable damage to their armatures. I suspect they aren't drawing as much as this though...

 

Cheers,
Alan

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Just seen this thread.

 

I have attempted repairs to quite a number of these over the years. In many cases the motor assembly becomes misalinged, leading to overheating.

What seems the bigger problem however is the small plastic spur gears which split in half or just on one side. Even a split or crack on one side of the gear will cause the mechanisim to 'click' when running or to jam completely.

Unfortunately Bachmann no longer have spares and most 'spares or repairs' stocks or listings probably have the same problems.

 

Jim

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Unfortunately Bachmann no longer have spares and most 'spares or repairs' stocks or listings probably have the same problems.

 

Jim

 

BR Lines have spares. Bachmann did the last time I tried also. Unlikely however to be the cause of the problems described on at least some of these models as the Hall, Merchant Navy etc all have 25 tooth drive gears that very rarely split.

 

Split gears are easy to fix and should not render a loco scrap - only a few occasions where the motor has been left with power on while the mechanisms is seized due to the gears will the motor get very hot, first melt it's bearings (easy replacement - only a few £) or at worst burn out (even this, the armature can be replaced).

Best,

Alan

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