ok so my mexican strat has gone a bit odd, the action has gone, i put some heavy bottom strings on it and the bridge has pulled up. i have no idea about string gauge etc (an explination would be great). yeh so basically the action has gone, dont think the neck has curved. even when i do loosen the strings the and the bridge is back to norm the action is still pretty poor. thanks.
The higher string gauge has put more tension on the bridge, 'cause it to lift.
On the back of the guitar there's a plastic trem cover, open this up.
There should be two screws going from the trem claw into the wood, tighten these up until the bridge has returned to its normal positioning
you may need a setup and unless you are tuning down the action will be stiffer because the strings are heavier.
If that doesnt work, you may need new springs. Mine went after a while too. Easy one to fix.

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