Just having done battle last week for two days in a confined space (aka chain locker) to remove my anchor winch
(Simpson Lawrence Sprint 1500) I feel qualified to offer my 2d.
First off, visit the web & get internal drawings of parts
of your winch
. What brand is it? However, I think the general principles remain the same.
drum should usually lift
straight off the shaft to expose the upper half of the clutch that engages the chain gypsy
when you tighten the top winch nut. This clutch half is held onto the shaft by two keyways. Your rope
drum may have rusted / welded onto the upper clutch half which is secured by these keyways. Hence your immovable rope drum. The clutch halves are brass domes & will wear over time and need to be replaced if the gyspsy starts to slip under tension. If that slippage has been happening for a while and you have been overtightening the top nut, the rope drum could well have welded itself to the upper clutch dome.
If this is the case, you would be best to remove the entire winch including motor
and go to a workshop to use a press. When my winch jammed because the main shaft bearing had got wet and rusted tight, it took 8tonnes of force to get the shaft out of the gear
Nigel Calder's book "Boat owners Manual" has a good section on anchor winches. No boat owner should be without that hefty tome on his floating shed IMHO
Good luck, dude.
PS I am off now to initiate some Pollywogs at a line crossing, just passing Karimata Islands off Kalimantan, Indonesia
on a VERY slow rig tow to Cape Town