No, it won't work fine with 120 film. It will work somewhat but it's made for 220 film which is twice as long and half as thick.
Originally Posted by edmyloo
Forget the timer. You can test the shutter well enough by setting at 1 second and releasing it and counting "one one thousand."
What you should bring is a small flashlight. Set aperture to widest setting and shutter to "B." Open the back, and shine the light through the lens while the shutter is held open. If there is fungus or haze in the lens, forget it (unless you want to fix it yourself. If just some dust specks, it's OK.
But, I really don't think buying a Yashica 24 is a good idea for a newbie. Almost any other 120 film Yashica TLR would do much better IMO.