Can someone tell me the difference between static and mechanical timing and how to check mechanical timing?

I assume you are talking about distributor advance. Static timing is wherever you have your distributor locked down at e.g. 10 degrees BTDC. Mechanical advance uses weights and springs to advance by centrifugal force within the distributor. This mechanical advance can add 20 degrees. To find your max mechanical advance, you need to have a timing tape or dial back timing light and rev the engine until no more advance is observed. I hope this helps.