Small Engines (Lawn Mowers, etc.): McCulloch Pro 610 Clutch, friction linings, clutch assembly

Question
Hi, I have a McCulloch Pro 610 chainsaw, that appears to have a slipping clutch. How do I remove the nut holding the assembly to the crankshaft? If I remove the starter cord assembly anf hold the nut on the other side, it is that nut which loosens! Is there a special too to lock the clutch assembly whilst undoing it's retaining nut?
Secondly, on first inspection, the clutch doesn't appear to have any friction linings, is this correct? If so how on earth does it grip metal to metal? If It sould have friction linings, are they visible before removing the assembly?
The symptoms are that whilst cutting with the saw,if the chain hits resistance in the wood it will stop, yet I can still increase the engine speed! Seems like a slipping clutch to me!
I will be most grateful for any assistance.
Cheers,
Tim

Answer
There is a special tool but you can do the same thing with some string.  Use a piece of starter cord and tie some knots in the end about 12 inches from the loose end of the string.
Remove the spark plug and insert the knots thru the spark plug hole.  Sometimes you have to use 2 or 3 knots.  As you try to remove the clutch nut the piston will eventually stop as it hits the knots.

Use a flashlight to check the clutch and clutch nut...sometimes they are left hand threads...it's been too long and I can't remember.

As for the clutch, the inside is metal with some springs and the drum is metal.  As RPM increases the inner clutch overcomes the spring force causing expansion which grabs the outer drum.

There will be a needle bearing assembly in the clutch along with a washer on the back side of the cluth.  Make sure the washer is flat and not bent.  Bent washers were common on 610's which would wear the seal.

Let me know if this helps.
Eric