I've been living in this colonial for about 13 years. The upstairs toilets have worked OK up until about 6 months ago. I have two bathrooms upstairs, on the far sides of the house. Now, they both fill up with water, swirl a lot, but never completely flush. The toilet on the first floor flushes fine, as it always has. All the drains in the house work fine as always. I've plunged and plunged, but never brought anything up, or made them flush any better. The toilets are all about 30 years old, so there's no 'kicker' hole at the bottom of the bowl. Please help!

You have gravity or wash down toilets. You have some sort of a back pressure problem that's not allowing the bowls to siphon. Have you felt up in the opening for mineral deposits? If you have a mineral build up perhaps the bowl needs to be boiled out or replaced. I would first purchase a toilet auger and auger out the bowls. If that doesn't help click on back. Good luck, Tom

Just a quick thought Mike... lift toilet tank lid off and put someplace safe.

Then flush the toilets in question but this time hold the flapper up and don't let fall until toilet flushes or tank empties.

If they flush much better it may be that the flappers have gone bad... I have only seen this a couple times in this way... but when I replaced the flappers with some of the newer, universal models, problems were fixed.

Try the test... look for minerals, try the auger, etc. that Speedball suggested... get back to us... Mark

Ok, All the vents on the bottom of the rim are clear, I stuck a little screw driver in them to be sure. The trap in the toilet seems to have a very sharp curve in the rear, I can't get my snake through there. Do they make a tool just for such a problem? I'd hate to take them off the floor to look down the drain pipe.
I held up the flapper valve and there is no appreciable change.
Could the sewer vent for the house be blocked? Even though I don't get any backups from showers, the dishwasher, or the Laundry tub?

The toilet snake Tom mentioned is called a closet auger... made just for toilets! Looks like the pic.

Perhaps a vent is clogged with say leaves, bird's nest.hmmm.. But try the closet auger first (can buy at home depot for $30.00).

Let us know

And here's how they're used. Good luck, Tom