puzzling toilet innards

Never seen a housing around the flush valve like this before.
Looks like a home made make shift water saver device that will reduce the amount of water per flush. Personally I would put a complete rebuild kit in it.


Those holes around the flapper are there to equalize the water level between the inner housing and the whole tank. If you still have water leaking into the toilet bowl, it is coming from a leaking flapper.

I seen a lot of early water saver toilets that were like that in the early 90's. That was right after the 1.6 mandate was first introduced. Think some manufacturers just took regular toilets and converted them to use 1.6 gal, most flushed really poorly. Well designed toilets using 1.6 or even 1.2 can flush really well, they'll have larger flush valves and larger traps.

All the water that leaves the tank has to either go down the flapper valve or down the overflow tube. The Flapper is likely the problem, but it can also be the flapper seat. The seat can crack or get deposits on them so the flapper doesn't seal correctly. You can buy a repair kit that epoxies a replacement seat over the old one but never had great luck with them, better to just pull the tank and change the whole flush valve assembly. None of the parts are very expensive, just a bunch of messing around, getting old bolts out and cleaning up everything. With an early water saver like that I'd probably just replace the whole thing with something a lot better.