can I use a MAPP torch to use to sweat 1 1/2

I can be done if you know what you're doing. As always, clean, dry, and properly fluxed (and enough heat in the right place) are the keys to success. It can't hurt to practice first. You also might want to investigate the cause of the leaks. Is the connection failing (workmanship) or is the fitting or pipe itself failing (turbulence or corrosion)?

This is L type copper, and all the leaks so far are at elbows and tees/reducer. 1 leak was at the joint, one was the wall of the elbow itself, and the other, I haven't seen up close yet, but it is right near the elbow.