Pulling cog off Albion Type C gearbox

[Ian Whittaker 3Participant @ianwhittaker3]

Hi, I have an 1923 Albion gearbox and I am trying to remove the cog to replace it with a V pulley. Does anyone know how to remove it, as I am not sure if the metal ring which retains it is threaded or if it is held by a woodruff key?? Attached is an image of what I have. If it is threaded any practical tips on how to stop the cog rotating whilst I try to unscrew it, would also be appreciated.

[Ian Whittaker 3Participant @ianwhittaker3]

[Oily RagParticipant @oilyrag]

Hi Ian,

A warm welcome to the forum.

An image would certainly help in understanding your problem, and it appears you may have tried to post a picture. There is a link in the FAQ's (or somewhere! ) but essentially you have to create an album and then click on the camera icon on the above toolbar in the 'Add Posting' pop up to post with text. An odd quirk is that you can continue typing after posting a picture but it is best to hit carriage return to get the text on the next line down. The photos can be loaded only 5 at a time to your album and there does not appear to be an upper limit of photos you can have in your album. Jason will be along next to put me right on this I'm sure; overall it is pretty easy once you get used to it.

To hold the sprocket(cog ? ) can you wrap a length of old chain around it and secure in a vice. That will secure the cog (sprocket ) whilst you then drift, C spanner, or whatever is holding the cog. If its threaded there may be a visible sign of a thread at the ring shaft interface. Clean it up well and it should be obvious what the fixing system is.

Martin

[Ian Whittaker 3Participant @ianwhittaker3]

Hi Martin,

Thanks for the reply and info re using chain, never thought of that!! Here is a picture of my predicament, I can't tell if it's threaded, or held on by woodruff key etc and just need prising off the spline?? I have had a good look and can't see anything obvious such as a thread, or markings which gives us any clues!! I was hoping someone had had the same problem before and had the answer, or if not potentially a manual etc, to give us the answer that way.

The gearbox is an Albion Model C FeatherWeight model 1920's, which has taken me a few months to track down, so obviously not resorting to a hacksaw at the moment!!

Thanks for reading and allowing me to join the forum!! – Ian

Edited By Ian Whittaker 3 on 29/10/2021 13:57:28

[Dave HalfordParticipant @davehalford22513]

Might just need a gear puller the sprocket is a serviceable part.

[Brian WoodParticipant @brianwood45127]

Hello Ian,

This might be a case of the sprocket being face driven by pin or pins from a shoulder behind it and the ring is there to hold things in contact. I would expect the ring to be screwed on using a fine thread, perhaps appropriately handed if the sprocket is normally turning anticlockwise

Regards Brian

Edited By Brian Wood on 29/10/2021 14:40:58

[Robert ButlerParticipant @robertbutler92161]

Assuming it's a motorcycle gearbox the National Motorcycle Museum list manuals and parts list for £3-00 – £4-00 or so.

Robert Butler

[Howard LewisParticipant @howardlewis46836]

Be wary of using a gear or bearing puller on the sprocket. It would be too easy to bend the teeth and ruin it!

You don't need to warned of the difficulty of finding a replacement.

A Woodruff key will only locate the sprocket in angular terms relative to the shaft, it is not a retaining device.

You need to decide how the disc at the front retains the sprocket. Look VERY carefully at the boundary between the disc and the shaft to see if there is a thread.

Then you have to try to work out whether the thread is right or left hand. Once you decide on that the problem is how to hold the disc to rotate it relative to the shaft.

As suggested using a chain around the sprocket can be used either to hold the sprocket stationary while the disc is slackened , or to rotate the sprocket and shaft around the disc while it is held by a strap wrench, or in the jaws of a vice.t

Once it apart, you may decide to depart from prototype, by making a pin spanner and drilling two holes in the disc to match the pin spanner.

Howard

[Oily RagParticipant @oilyrag]

This may sound daft – but is it retained internally? Being a small gearbox may be that you can get inside of it and find if there is an internal nut on the other end of the disc. Just a passing thought!!

Martin

PS – And I thought it was a Lorry gearbox – doh!

[Robert ButlerParticipant @robertbutler92161]

I would refer you to my earlier post.

Robert Butler

[Dave HalfordParticipant @davehalford22513]

Where are the holes for a pin spanner or flats for the spanner if the disc is threaded and intended to unscrew from outside there should be something.

Is the disc bruised by a hammer it looks a little battered.

I must say £2.59 is an outrageous price for a parts manual but the C appears to be 1930 and the featherweight is all versions.

[Robert ButlerParticipant @robertbutler92161]

£2.59 outrageous??????? less than a pint.

Robert Butler

[Peter Cook 6Participant @petercook6]

Don't know if it will help, but there is a (slightly bizarre) video on YouTube at Manual – Albion Gearbox – YouTube which shows what looks like a similar box being reassembled.

The cog on that one is splined on, and seems to have a threaded retaining nut. Could the damage pointed out by Dave be the result of someone using something like gland nut pliers to get the nut on/off?

PS all the images I can see of Albion gearboxes seem to have the same or similar output shafts with splines for the cog and a retaining nut. So my money would be on that ring being threaded on.

Edited By Peter Cook 6 on 29/10/2021 19:07:01

[old martParticipant @oldmart]

It looks to me that the nut has been worn down or modified sometime ago. I would look closely at the marks on the side to see if any sign of a thread is present. There is a chance that it has a left hand thread.

[Ian Whittaker 3Participant @ianwhittaker3]

Hi Guys, thanks for all the posts, I didn’t expect so many, so thanks!! I have got a parts list of the gearbox from the motorcycle museum and it doesn’t show enough detail to work out of it’s a nut or not, as the brochure is literally all the parts in the gearbox, but not in the order they are put together, or sufficiently detailed so show any threads etc.. I cannot see any nut/bolts on the inners to release it from the inside. I guess I will have to lock the spindle as suggested and try some brute force on it trying to turn it, after giving it a good dose of wd40 etc to soak into any threads etc..

Edited By Ian Whittaker 3 on 29/10/2021 20:41:29

[roy entwistleParticipant @royentwistle24699]

Ian Use Plusgas instead of WD40 use the liquid instead of spray if you can find it

Roy

[Robert ButlerParticipant @robertbutler92161]

Drill two holes on the diameter and create a pin spanner to suit, or drill one hole on the perimeter for a C spanner.

Robert Butler

[David CauntParticipant @davidcaunt67674]

It certainly looks like a thread. Possible it is a left hand with what is just visible

[Swarf MakerParticipant @swarfmaker85383]

I doubt that Albion did anything radically different to any of their other gearboxes – or indeed other gearbox manufacturers. The sprocket will be on splines on the output shaft which is integral with the top gear – together known as a 'sleeve' gear. The sleeve gear will carry a normal RH thread, thus retaining the final drive sprocket. It is normal for there to be a locking washer that mates with the splines and allows a segment of the periphery to be turned and locked against the sprocket nut. The nut on your gearbox has been replaced with the battered ring but should still be threaded – unless something dire has occurred to the sleeve gear in which case this ring may be locked in place by deforming things or with some adhesive type locking compound. A ring without features to enable it to be 'spannered' does seem a bit strange though.

[David CauntParticipant @davidcaunt67674]

The marks around the edge look like a large Stilson has been used to turn it.

[Nick Clarke 3Participant @nickclarke3]

Posted by David Caunt on 30/10/2021 00:25:06:

The marks around the edge look like a large Stilson has been used to turn it.

But take care they could also be marks where a a large stilson has TRIED to turn it and failed!

[HacksawParticipant @hacksaw]

A friend of mine went into Muffetts ,Tunbridge Wells, to ask about having a cog made . .. They said No ..cogs are made of wood…

[Chris GunnParticipant @chrisgunn36534]

This looks a bit like a torque limiter we used to use many years ago, which had fibre friction discs between each side of the sprocket and the disc on the outside, and the hub on the inside between chainwheel and gearbox. However the ones we used also had a fine threaded locknut holding it all together. there appears to be a gap between the outer disc and the sprocket which could indicate that. The hub was located on the shaft with a parallel key, and grub screws through the hub.

Chris Gunn

[not done it yetParticipant @notdoneityet]

My initial thought was whether it was (originally) a free-wheeling sprocket?

[Ian Whittaker 3Participant @ianwhittaker3]

SOLVED!! I took the step of drilling a slit in the metal disk, and locked the gear with my vice. Then with hammer and chisel tapped the disk (using the slit) in an anti clockwise direction, as this seemed to have more movement. As I tapped it became much easier and appeared to be threaded after all. Once it came off the cog underneath was Visible, but again it is threaded onto the shaft. It appears a small piece of square metal acts as a key to stop the thread from being turned, but once removed and the underneath cog is locked, to stop movement, this can also be tapped free, in an anti clockwise direction!! Once done the inner cog is released so I can clean it, and replace the outer cog with a new v pulley!! Thanks for the info, and if the above helps someone else out, then happy to have done so!!

Ian

Edited By Ian Whittaker 3 on 01/11/2021 17:20:16

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