Blade attach part

[jalin6]

How do you remove the part the blade attached to from the crankshaft of an old mower with a B&S 6bh engine.. Does it screw on the crankshaft and if so, right or left threads?
This mower must be 20 or 30 years old.. Any help will be appreciated.

 

[ILENGINE]

They just slide on the crankshaft with a key to hold it in one place. It is not uncommon for them to rust to the crankshaft. You may be able to use a puller to remove the blade mount, but may also need a lot of penetrating oil and sometimes some major heat.