Not an easy job. These clutches may (or may not) have been on there for 50-odd years and some more than others are reluctant to come apart.
I am indebted to Barrie for his postings which put me on the right track - the most important being the fact that the outer aluminium bell housing is threaded on, and IS LEFT HAND THREAD (ie: clockwise to remove). I looked at Barrie's instructions (involving wedges, time, and drinking tea??? WTF) and thought (respectfully), there might be a better way.
So I did a bit more research and then took the time to document what I did, for the benefit of those dealing with the same thing in the future.
First of all: the different clutches used on Hus ski's:
- the very early 200 (very rare) - Powerflo made by the Morse Chain Co. - uses 5 steel balls to move the outer sheave;
- 200(A) - relatively common - uses a proprietary clutch (made by Hus ski) - ** this is what I was dealing with, and is the one pictured below**
- 444 - uses a Salisbury 500 (this is a clutch assembly purchased by Hus ski from an outside manufacturer - in this case, Salisbury, who was the guy that developed the concept of the CVT clutch. I have worked on these in the past, and some of the techniques below may apply.
Step 1 (not pictured): remove clutch retaining bolt - standard RH thread (counter-clockwise to remove), 1" socket required;
Also: I had the motor bolted onto the cast aluminium motor mount, and clamped to the bench - and had put a rope into the cylinder to keep the crank from rotating.
Step 2 (photo 1) - make a special holder that will bolt onto the two bolt holes in the outer bell housing - in my case I used an old motorcycle fork tube as an extension. I used a propane torch to heat the area prior to using gentle pressure - REMEMBER, THIS IS LH THREAD ! CLOCKWISE TO REMOVE ! One of mine came off cleanly. The other was stiffer and some of the aluminium thread was left on the steel inner sheave threads. There isn't a lot you can do about this. Steel and aluminium do not like each other. Use heat and patience (turn off a bit, then back on, then off some more).
Photo 2: this is what you will see once the outer bell housing is off. Remove the guts of the clutch and clean up the threads as best you can. Then use oil, and carefully thread the outer clutch bell housing (no guts) all of the way back on. You will now use the bell housing to pull the inner sheave off of the crank (taper, with a key, see below)
Photo 3: Once the bell housing is all the way on the inner sheave, use a common, universal puller, installed as follows: (as with this whole procedure, lots of lubrication (on the puller), and patience and a precise feel are necessary. Tighten the puller, hit the end of the bolt, tighten some more. I have a luck as well with tapping on the sides of the puller. One of my inners almost dropped off on it's own. The other required a lot of force, and I heated the inner with an oxy/acetylene torch until it was red hot. It still took a lot of persuasion (time, patience, etc.)
Photo 4: this is what you will see once the inner sheave is off, exposing the crank seal for replacement. These can be pried out relatively easily.
Photo 5: clamp the whole assembly to the bench. Remove the puller assembly. Then turn the outer bell housing CLOCKWISE to remove it from the inner sheave.
Finally, as mentioned in the beginning, this is a challenging job that requires a balance of force and finesse. Take your time, use heat as necessary, and lubrication. It is not something that I think should be tackled with a cup of tea! It's a serious job, so get serious - this is the after photo:

I am fairly new at posting photos etc. Hope this works, and hope this is of assistance.
If anyone wants to add there 2 cents worth, or if I stand corrected on anything here, please chime in.
Mike O'Reilly
Constance Bay, ON