#1
I recently bought a 1974 Epiphone ET-270 at a guitar show. I'm restoring it but the tremelo bridge won't dive you can only bring it up. I looked at the springs and they are fine. I was thinking that with string tension it would float but it doesn't. If anyone has any ideas please let me know.
#2
only thing I can think of is that its not routed correctly for the trem.if you cant push down on it, it means wood is preventing the trem block from going back.

also, sounds like a strat-style trem as opposed to a floating trem. it may never float the way you want it to.

however I abuse my strat trems all the time and they can take a decent beating if you clamp down on the springs and push harder with your hand. believe it or not, having more than zero point tension works great if your only diving down from my experience.
Gear:

Jackson dk2m
MIM strat
peavey jsx 2x12 combo
Recording King RDC-26
Digitch RP1000
Crybaby 535Q