I have a Mexican Stratocaster that won't keep a tune. As I try to tune it, the bridge with a tremolo keeps rising. I took the back cover off and replaced the springs with this Squire Strat I have and it doesn't make a difference. Now what's funny is I put the Mexican springs in my Squire and now it's doing it too. I've never had this before.

Should I turn the two screws on bottom that mount the springs deeper into the wood?
In short, yes.

Spring tension = String tension.

If you are not using the tremelo arm you can tighten the claw until the bridge rests on the body when tuned to pitch.

If you are using the arm then a rise of 1/8 inch at the back of the bridge is fender spec. It allows you to flatten and sharpen the note with the bar.

Check dis out: Fender Stratocaster Setup Guide
Last edited by spicyfourpiece at Jun 14, 2014,

You need to balance the string tension with the spring tension. Just tune your guitar(the bridge will rise, it's normal) then adjust the springs. then tune it again and repeat until your bridge sits perfectly flush with the body.
Did you replace the springs or add them? The guitars don't come with a full set of springs I don't believe. Do you see places to add more springs? Add more there. Or place them diagonally, increasing tension.

If you aren't using the tremolo, then you can "block" or "wedge" the tremolo. You can find videos of it online. Basically you slip a piece of wood in so there's no way it can move. This makes it so the tremolo will never move during anything, from tuning to bending
I added a few springs from the Squire so now there's 5 springs in the Mexican Stratocaster. I'm just worried with all t hose springs in there, that if someone plays it, and messes with the whammy bar, they may pull the screws out of the wood.
The full travel of the trem is not very far, no chance of pulling the screws.
If they are too loose already, you should rather tighten them instead of adding springs.
I've got 12's on my strat with a floyd only using 2 springs. Turn those screws in.
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