I have an issue about some type of plunger stuck inside the overflow assembly. The tub is older and the overflow cover plate was gone and the entire assembly was missing when I got to the tub (helping a friend). I know there is something in the overflow assembly because I sent a plumber's snake down the overflow, pushed past a little resistance and the tub drained, almost as if I had pushed past something. I pulled the snake out and ever since then, I can't push the snake down anymore and the drain is completely blocked. With no assembly attached to the plunger, is there anyway I can retrieve it without going behind the tub or under the house? I tried coat hanger retrieval, I've tried the snake again and I tried WD-40, but to no avail.
Soak it overnight with CLR to soften any lime/scale (the bucket, i.e. stopper will often have crusty stuff from years of just sitting there) then douche it with penetrating oil like liquid wrench. Then use a stiff heavy-gauge wire bent into a hook shape to try to fish the bucket out.
Then, instead of trying to replace the bucket and wire assembly, leave it out and put a blank trim plate on the overflow. Hand them a rubber stopper and scram before there are additional problems.