Allen scythe removing the wheels

[rowan-bradley]

Can someone please explain exactly how to remove the wheels on this machine? Or perhaps more importantly, what stops the wheel coming off in normal use? My machine has the ratchet axle. If I look at the hub, there is a hex socket headed grub screw in one side. This is surely not enough to hold the wheel on in normal use? What is its function? I have not tried removing it yet, but I will when I have found my box of allen keys. And on the other side is the gib key. I think I can see how to make a holder to attach the end of this to a slide hammer, without welding it on (as someone suggested). But somehow neither of these seems man enough to keep the wheel in place through thick and thin. Is there a taper somewhere that holds it? Or what? If I remove the grub screw and the gib key, does the wheel just slide off? Or come off with a few hammer blows to the inside of the wheel? Or do I have to do something else to release it? Does it need some kind of puller?

Thanks – Rowan

[rowan-bradley]

I am still struggling to remove the wheels on this machine. Mine does not seem to have hex grub screws in the hubs. I think I can see the surface of the axle at the bottom of the hole. So either I removed these screws in some previous attempt (and forgot doing it), or it never had them when I got the mower. Does anyone know what the thread of these screws is? If so I can try to replace them.

I have tried hammering a steel wedge into the gap between the gib key head and the hub, but the key has shown absolutely no sign of moving. This seems to me a pretty drastic treatment, and if this did not move the key, I’m not sure that a puller would do any better.

Can anyone suggest a more effective way of getting these keys out? If I can’t shift them, then the mower is basically scrap metal 🙁

Thank you – Rowan

[charlie]

Have you tried heating the wheel around where the key is. In addition to expanding the metal I have found the heat helps breakdown rust. Very likely, as suggested in another post on the forum, the gib key has been hammered in too far previously.

[davidbliss]

yes like Charlie said heat helps, but be careful if its a large lump of cast iron, heat, soak with paraffin or WD 40 and walk away, do this several times is better than loosing it and trying to do it in one hit. Often people try removing the key with an ordinary chisel, it may work if not tight but does harm to the key head, I use a C shape key remover its inner edge is chamfered so it pulls down into the base of the key head so it can generate a good pull without bending over the key head. With experience and if I feel its going to be very tight I weld on a piece of threaded rod, using a piece of pipe to bridge the shaft so one part is being pushed back while the key is pulled, have made a bridge so can use the key drawer at the same time. Sometimes pulleys can be driven further back onto a shaft again its a be careful and have drilled down the length of a key and works, however keys are normally tough and if you start drilling wrong, you could destroy the lot.Photo note the curved and chamfered shape.

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[charlie]

It is also worth using a penetrating fluid such as Plus Gas rather than WD40.

[andyfrost]

Gib head keys are tapered , the idea , provided an amateur hasn’t been at it , is to knock the hub on further , heat may be needed , once you have moved the hub , the key should release relatively easily.
The difficult part may be if someone in the past has assembled it and pushed the hub fully on before tapping the key in.

Andy.

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