Originally Posted by Bluedoo42
.. There is a pin next to centre bolt I'm guessing has something to do with it maybe a key lock of some sought again I am very amateur at this
The pin that your on about is called a Woodruff key & is usually half moon shape "D " Google woodruff key ") which locates in a slot on both the flywheel & usually a Tapered shaft It stops the flywheel slipping around on the shaft & stops the ignition timing /point s getting out of position , You wont be able to remove the key until you remove the flywheel first , the shaft is usually a Tapered one & the flywheel can be hard to remove or take off , And it needs to come off straight , you can be lucky by slacking the large nut having someone to lift or take the weight of the engine by holding the flywheel & then giving the nut a crack with a hammer ,,, though its easy to knacker the shaft thread or nut . The best way to get the flywheel off is after you have slackened the large nut is to use a proper puller with legs or you can make one from a thick heavy piece of steel plate with 3 holes & bolts to match those on top of the flywheel then tighten them up a little at time but watch the bolts dont go down too far as they can damage or screw themselves in the coil when tightening up .your local garage should have something to fit .