freewheel washers Shimano 6 speed MF-Z012
 

I was removing a freewheel and wasn't paying enough attention. The freewheel fell to the ground and 3 very thin washers fell out as well. Two are very thin, and the other is about three times as thick as the other two. I'm guessing they sit on a groove on top of of the hub (see where the tip of the cone wrench is resting on top of the threads for the freewheel.).Is my guess right, and if it is, is there an order that I should stack the washers? e.g., thick one on hub, followed by the thinner two?

https://cimg4.ibsrv.net/gimg/bikefor...876162091a.jpg
https://cimg3.ibsrv.net/gimg/bikefor...7d84bb7e15.jpg

Those washers look like Sturmey Archer cog spacers. They were used frequently to space out freewheels on the hub's threads (for various reasons). The spot indicated is where there's usually a dust cap that either is pressed into the seat or it a close clearance fit within (and in pressed onto the cons instead). As to the order of the FW spacers- place the thickest one on the hub's FW threads first, better to resist the molding nature that can happen between the shell's seating shoulder and the FW back side. Andy

The bike was used. (a fairly nice Ross Centaur that I got for 20 dollars) As I think about this more, the spacers may have been installed incorrectly. (the wheel and hub are not original to the bike, but the freewheel may be). I saw a youtube video that mentions the spacers like mine (see video starting at 8:17) The freewheel needs to be disassembled in order to get to the spacers. The spacers, according to the video, are so that the free wheel's lock ring (the one that shows the brand and model of the freewheel) does not smash the freewheel's ball bearings.

What?? Your show a hub shell FW threads and say nothing about taking the FW apart but do say the spacers fell when the FW was removed from the hub AND now talk about the FW core being taken apart. Which did you do to find these spacers? Have you tried to fit the spacers/washers to the various parts yet? Andy

I posted my last post after I saw that video and learned about the spacers. I started wondering if the previous owner did some freewheel maintenance and disassembly and did not put the spacers back properly. When I spun the freewheel, it did feel like it was catching on something, which increased my suspicion. But I did end up taking apart the freewheel, and saw two spacers, just like in the video. The spacers were the same diameter as the ones that fell out when I removed the FW from the hub. I guess they do go where I first thought they went: in that groove on the top of the hub shell threads.

I agree with Andrew that these appear to be Sturmey-Archer hub spacers. BITD, we'd use them to adjust the chainline by either putting them between the freewheel and hub to move the freewheel outward, or between the fixed cup and bottom bracket shell to move the chainrings outward. Not sure why you'd need three of them on the hub, though.

Ok... A little confused... Were these spacers fitting over the threads on the Freewheel to move the Freewheel out from the hub? I have had to use spacers like that to move the Freewheel out to engage the derailluer properly.

Or... Did you find these spacers when taking the Freewheel apart? And were they in-between the Cogs on a complete disassembly?

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...in your picture, it appears you have not disassembled your freewheel to access these spacers. You don't really need them on the bub, to space the freewheel a little farther out. Nor do you really need that spoke protector thing. Just service your hub as you were planning to do, and lube the freewheel by dribbling some oil into the open crevices between the cog body and the freewheel body that screws onto the hub.