Few problems on "new" tt

I just bought a Sansui sr-222 turn table, and, of course, there are a few problems... I just hope you guys can help me out.

First, it sounds awful... I gues the cartridge is'nt in to good a shape, but I could'nt tell (because I know nothing about turntables). It sounds "heavy" : the bass is kind of deap... The cartridge is a ltd-250 (?). I did not find any information on the setup (weight) it requires. If anyboby as any idea.
I will soon buy a knew one, but if I could have working meanwhile...

Second : it grinds. The belt seems to rub on its guide (speed selector). I tried to chang the adjustment, but it also changed the speed. So I set the speed again, and its noisy again. I tought about trying a silk wire.

Also : the motor shaft is spring loaded (I did not know that :-) ), The belt pulls on it when I start the tt, but on the short (and less restricive)side of its float, causing the shaft to rub on the rake (speed selector) and the belt to move on it. Could it be mounted with the float pointing in the wrong way?

I know these are pretty technical questions, and not fun to anwer at all. If you could help me, though, I would be glad to get to know how this thing works.