Split drive gears on Grafar / Farish N gauge locos and (particularly) DMUs.

[Justin Smith]

Am I just unlucky ?
I have bought five Grafar-Farish N gauge locos/DMUs off E Bay and three had cracked gears, that's 60% !
Both the DMUs I purchased had (I think) cracked gears, that's 100% of them ! I think they were Grafar types (Poole built but plastic cogs ? ). One only moved about 6" then locked up completely, the other (which I have only just received) works but is noisy and "clicking" on one bogie as it runs. Would I be right in thinking it is only a matter of time before the latter locks up completely ?
Of the three Grafar/Farish Locos I bought two were OK but one (a class 25) was clicking and occasionally locking up, fortunately the seller of that was experienced and said send it back and he would repair it and send it back to me, which he did.

Am I right that cracked gears are reasonably easy to repair ? I believe the spares are available from :

https://www.farishnspares.co.uk/graham-farish.html?page=all

Should you replace all the gears in the drive train ?
Or should you buy the axles c/w gears ? But the axles are about a fiver each, so four (incl carriage) would be not far off £25 !

Class 108 DMU gears ?
https://www.farishnspares.co.uk/gra.../-width-1-94mm-/-shaft-size-1-56mm-b2515.html

Not sure what this means :

PLEASE NOTE do not mix silver rimmed wheeled axles with the later Chinese wheels otherwise heat damage to armature will occur. However they will retro fit - ensure they have free sideways movement in their respective slots.

Does that mean replacing all four axles will be OK, even Chinese types on Poole built DMUs ?

 

[Justin Smith]

Farish / Grafar Class 101 DMU split gears Rebuild

I have just rebuilt the drive gears on a Farish class 101 DMU. It was "clicking" whilst running, a sure sign one of the drive gears (usually the ones on the axles) has split. This can be confirmed by trying to move the gears sideways on the axles (with moderate pressure), if they move they're almost certainly split.
You cannot buy the original Poole built axles anymore (and they're not "splittable" to allow just changing the gear) and if fitting Chinese replacements it is recommended you replace all 4. The Chinese axles are splittable if the problem ever returns.
When rebuilding care should be exercised not to bend the spring/brush that allows current from the wheels to reach the chassis. If this is bent then it catches on the chassis and the bogie will not move freely, plus the current may not get through anyway ! One of the accompanying pictures shows the approx position they should be in before reassembly, but watch carefully as rebuilding, hold it in the correct position with a pin or similar if necessary.

Second point, the inside bogie is reversed, and the coupler fits in an odd manner. I did not take too much notice as I stripped it all down and then had to spend ages trying to work out how to reassemble it ! That's part of the reason I have put this article on because I could not see any pic of it on the Internet in the time I had to search, some pictures before full assembly and after are attached. It's a good idea to mark which is the front of the chassis.
I also replaced the 4 sets of current collector springs and the 4 intermediate drive gears as they weren't particularly expensive, particularly as I'd already paid the postage ! All in the parts with P&P and VAT did cost £28.40 though, so if buying a unit that requires repair that is worth considering !
Bob Russell at BR Lines if very helpful if you phone him with any problems.

Note the bogie frames unclip from the "blunt" flat end of the bogies.

BR Lines part numbers :

Drive axles (Chinese) - GF7101-2 - £3.50 ea + VAT
12 tooth intermediate gears (set of 4) - GF2503 - £3.50 + VAT
Set of pick ups (4 sets) - GF0007 - £2.92 + VAT
Carriage 1st class - £3.85 + VAT

Farish Class 101 chassis


Farish Class 101 inside bogie coupler - underside (before clipping on the bogie side frame)



Farish Class 101 inside bogie coupler - topside (before clipping on the bogie side frame)


Farish Class 101 inside bogie coupler - topside (after clipping on the bogie side frame)


Approx position of current collector "wipers" before assembly on Farish Class 101

 

[Cowley]

Farish / Grafar Class 101 DMU split gears Rebuild

I have just rebuilt the drive gears on a Farish class 101 DMU. It was "clicking" whilst running, a sure sign one of the drive gears (usually the ones on the axles) has split. This can be confirmed by trying to move the gears sideways on the axles (with moderate pressure), if they move they're almost certainly split.
You cannot buy the original Poole built axles anymore (and they're not "splittable" to allow just changing the gear) and if fitting Chinese replacements it is recommended you replace all 4. The Chinese axles are splittable if the problem ever returns.
When rebuilding care should be exercised not to bend the spring/brush that allows current from the wheels to reach the chassis. If this is bent then it catches on the chassis and the bogie will not move freely, plus the current may not get through anyway ! One of the accompanying pictures shows the approx position they should be in before reassembly, but watch carefully as rebuilding, hold it in the correct position with a pin or similar if necessary.

Second point, the inside bogie is reversed, and the coupler fits in an odd manner. I did not take too much notice as I stripped it all down and then had to spend ages trying to work out how to reassemble it ! That's part of the reason I have put this article on because I could not see any pic of it on the Internet in the time I had to search, some pictures before full assembly and after are attached. It's a good idea to mark which is the front of the chassis.
I also replaced the 4 sets of current collector springs and the 4 intermediate drive gears as they weren't particularly expensive, particularly as I'd already paid the postage ! All in the parts with P&P and VAT did cost £28.40 though, so if buying a unit that requires repair that is worth considering !
Bob Russell at BR Lines if very helpful if you phone him with any problems.

Note the bogie frames unclip from the "blunt" flat end of the bogies.

BR Lines part numbers :

Drive axles (Chinese) - GF7101-2 - £3.50 ea + VAT
12 tooth intermediate gears (set of 4) - GF2503 - £3.50 + VAT
Set of pick ups (4 sets) - GF0007 - £2.92 + VAT
Carriage 1st class - £3.85 + VAT

Farish Class 101 chassis
View attachment 121560

Farish Class 101 inside bogie coupler - underside (before clipping on the bogie side frame)

View attachment 121559

Farish Class 101 inside bogie coupler - topside (before clipping on the bogie side frame)
View attachment 121557

Farish Class 101 inside bogie coupler - topside (after clipping on the bogie side frame)
View attachment 121558

Approx position of current collector "wipers" before assembly on Farish Class 101
View attachment 121556

Well I must admit that I’ve never had to do anything like this because I haven’t got any of the Poole era stuff (except for one carriage that I bought by mistake), but we’ll done for working out how to fix them.

 

[Justin Smith]

Whilst I'm in the groove..... :
I have a Grafar / Farish Deltic and it wasn't running as smoothly as it used to. I suspected contaminants had got under the current pickups / wipers (from the bogies onto the chassis), in fact I could see that two of the latter had been bent off forward of the chassis, not sure how that happened ! Readings on a meter confirmed they weren't S/C to the other bogies wheels as they should have been

Removing the bogies wasn't as simple as I'd hoped and hardly any of the Youtube videos I found seemed to be of the same "split chassis" type as my Deltic. This video (actually of installing a DCC on a Farish Western) is the same construction however.
As far as I can tell you have to split the chassis to remove the bogies so that's what I did. The attached pictures help explain the method.

A few things I learnt :
Mark the bogie locator blocks on the top so they go in the right place when reassembled I had a problem trying to put it all together, the bottom plastic spacer (which the "fuel tank" is screwed to) kept falling out, so I put a minute piece of blue tac in there to hold it whilst reassembling it. Make sure that it's so small it doesn't squeeze out and obstruct the motor above it.