Older toilet flushing problems

I have 3 30-year old toilets in the house and as years pass they all seem to flush with less and less vigor. Now they often don't completely flush. Otherwise, the house drain pipe system seems to drain freely. Also, the tanks fill to the top maximum level. Is this problem normal with age and if so can I fix it.

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Also, I should add, the tank fully drains during each flush.

Ill take a shot at this. The holes where the water enters the bowl under the rim have become caked with deposits of lime, etc. They need to be reamed out. Often a .22 cal cleaning brush is the right size to clean them up. Put it on a short section of cleaning rod and do not break it off. Good Luck, RW

Some folks may also put Lime Away down the hole directly under the flapper and let it eat on the deposits.

If you do the LimeAway (or CLR) treatment, put some duct tape on the underside of the rim to cover up the holes first - will keep the cleaning stuff next to the deposits longer that way.

Another trick is to bend a coat hanger wire at 90 degrees on the end and use it to poke the holes open. Can use a mechanic's inspection mirror (kind of like a slightly larger dental mirror) to get a look at the holes while doing.

Along with the holes under the rim, I once had to clean a "jet hole" (or whatever it might be called) at the lower-rear part of a toilet bowl. However the water gets into a bowl, it must come in quickly enough to get a good flush-siphon going. To see whether that is your problem, quickly pour about half of a five-gallon pail of water into the bowl and observe any difference(s) between that and a regular flush.