Re: Bought a bus - info wanted!
I'd say your cable is stretched. There should be enough adjustment there in order to make worn out lining hold. The only thing I found regarding thickness was this. "if linings are worn too near rivet heads, or are otherwise damaged, punch out old rivets and remove linings from brake shoes." In all honesty, linings should never wear out because they shouldn't be used to stop the bus, just to hold it. So if they are wore out it's because someone moved it with it still engaged.