Honda BF2D clutch will not disengage

Thank you but, I already have the service manual
"The truth is in there" (y).
Looking at it, if yours does have the centrifugal clutch, then simply disassembling it will reveal, and probably cure the problem. If there's this type of clutch, and the engine's not been used, or has been flooded and stored in a damp/salty environment, then the issue will be obvious. As it's a clutch, keep in mind that you'll want to avoid contaminating the friction surfaces.
It would appear that the actual engine does have to be removed from the outboard assembly to gain access to this, and if you're doing that you've then got access to the valves and the tappet clearances, so it's an opportunity to do a full service.
These engines are 'notorious' for not having stainless fasteners, so it could also be an idea to be prepared to simply soak the bolts in releasing fluid such as 3in1/WD40 or whatever your favourite is first, prior to having a go at this stripdown and repair.
I've only ever heard of these engines having the centrifugal clutch, but have seen reference to some BF2D not, and (perhaps) being direct drive.
 
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