#5 Overhaul: Shimano SIS Freewheel

The second in the series of overhauls for this blog with a in-depth look on how to remove, disassemble and reassemble a freewheel so be prepared for a long read.

Firstly before taking the wheel off the bike, if you intend on keeping the freewheel/wheel off the bike until finishing a restoration then remember it's much easier to take the pedals off the bike with the wheel and freewheel still assembled. Don't make the mistake of dismantling everything, putting it to one side then realizing the pedals are still on as you'll find yourself putting everything back together just to take them off. 
Once the wheel is off the bike then you will need the required freewheel removal tool, they come in many different shapes but if you Google what freewheel you have then it should show you what one you need. You can also search on eBay for it where you'll find an image and they should be pretty cheap, normally the older the freewheel the more expensive the removal tool. 
Once you have this tool then (depending if it comes with a built-in wrench) you will need adjustable wrench. Place the tool inside the freewheel while ensuring the freewheels teeth and the groves in the tool meet up tightly, then attach the wrench and turn anti-clockwise. It usually takes quite a bit of force (As when you pedal the bike the freewheel tightens itself) but if you are unsure then carefully add some penetrating oil and allow it to soak then try again. 
Once the freewheel is loose then you will be able to turn the removal tool by hand until the freewheel is almost off the hub. Be careful when unscrewing it from the hub, being careful not to move it too much on the threads. After this you should have the freewheel off the bike where it can be overhauled and also you will have full access to the wheel hub. (Which was overhauled in a previous post.)

The above image shows the removal tool used along with the adjustable wrench and removed freewheel. The other two above are the locking nut and spacer washer from the rear wheel axle. Now that the freewheel is removed it can be dismantled, cleaned then greased with assembly. 
This next step is important as here is a common area where people can ruin threads or seize the freewheel up for good and I find it poorly explained online.
To open the freewheel most instructions will tell you you will need to place a punch into one of the holes on the lock ring of the freewheel and then using a hammer and holding the center of the freewheel, hit the punch to turn this lock-ring anticlockwise. This is correct however, what most people don't explain is that if your freewheel is seized up or old then this is incredibly difficult to do, the difficultly being to hit the punch hard enough while holding the inside of the freewheel so it doesn't turn.  So ...

(Left) The removed lock-ring showing both manufacture holes where punch inserted. (Right) Freewheel with lock-ring and center removed. (both quickly cleaned but unfinished).

I personally find it much easier to mount the freewheel back onto the wheel hub as here the wheel hub will hold the center for you. Now you can hit the punch to turn anti-clockwise and as soon as you realize the lock-ring is loose then STOP. Here it would be best to remove the freewheel off the wheel as when loosening the lock-ring there are bearings under both this lock-ring and the underneath of the freewheel. Remove the lock-ring now by hand with the punch while holding the center and bottom. Now you can carefully count how many bearings are in the top and then the bottom, this particular freewheel had 32 top and 38 bottom and were as dry as a bone (see above). 
Here the lock-ring can be cleaned as sometimes they can be coated in old grease or rust. Also take this opportunity to thoroughly clean the freewheel teeth, I even went as far as using dremel tools on it and the results will show at the end.

 Here you can go to town on cleaning the freewheel, I used a number of cleaners and polishes for the best possible results. Look at the previous post to see a breakdown of all the tools and products for this. 

Now moving on to preparing and cleaning the center of the freewheel. The image below shows the center freewheel taken apart, all washers have been removed and also the lock wire and pawls. You don't have to remove the pawls as they can be a pain to remove and put back, removing them does make cleaning easier.

Note: Remember what order the washers came off the freewheel, use a zip-tie or some cord to tie them together. Normally the washers go on thinnest to thickest. I would not advise thoroughly cleaning these washers as they can break and bend easy. 
Call it obsessive but I find that the best way to clean the freewheel center body is with a dremel polishing tool and some of the stain/steel polish shown in the previous post. 
Once all the components have been cleaned then the next stage is to grease all necessary parts and assemble the freewheel. 

A useful habit to have is taking pictures of each process so you can remember the order that the parts assemble.

Here the parts are being greased with marine grease before assembly. 

First, Grease the bottom of the freewheel body and then one by one add all the bearings. The grease will hold the bearings in place. 
Next, Grease the inside of the freewheel (inside sprockets) and one by one add the bearings. 
Finally, lightly grease any threads such as the lock ring and VERY lightly grease the inside teeth where the pawls rub. Do not use too much grease in this area as it can cause the freewheel to 'gum up' when in motion or spinning. 

Note: Do not grease the pawls like in the image on the left, after doing this you will find that the pawls will stick to the inside freewheel body and will not function properly. You can add a thin application of grease but only to the bottom of the pawl and not anywhere else. When installing this component be sure not to hit the bearings on the inside of the sprockets part and make sure the pawls and the teeth line up. You will know if they have as when you spin the freewheel it will make a clicking sound, that's the pawls rubbing past the teeth as they should. When happy just screw on the lock ring and then tighten slightly with a punch and hammer, make sure the bearings still move smoothly just like in a wheel hub.

Finally grease the wheel hub thread and screw the freewheel on and you are done. It would be easier to overhaul, clean and grease the wheel hub first and if you haven't done, the previous post was this procedure.

Once the freewheel is on the bike then tighten down with the freewheel removal tool and tighten reasonably tight but not too tight as to ruin the threads. The freewheel will tighten naturally as the bike is used later. If I manage to find the original freewheel for the Raleigh Equipe then I shall upload another post with that overhaul.