I bought a universal tank repair kit and replaced all the innards of my toilet tank. The new rubber gasket between the tank and bowl is about 1/2 inch thicker than the previous gasket I removed. This is causing the tank to wobble and is a noticeable 1/2 or so from the bowl. If I tired to tighten the bolts down to force the tank to meet the bowl I would expect the tank to break. I could use the old gasket but the indentations do not match the new nut and it does not cover the entire downspout from the tank. Should I try to tighten with the new gasket? Should I give it a shot with the old gasket? Any other options? Thanks for the help.
1/2 inch is a lot to try and tighten it will probably crack you porcelain. Try looking for a tank kit or gasket with the labeling that it is for the brand toilet you have instead of just a universal. (Your toilet make can normally be found on the bowl centered by the seat hinge mounting) Look at the gasket an see if it closer to what you have. If you cannot locate anything else I would go ahead and try you old one. Make sure you get all the surfaces clean and dry (you make need to use rags to soak up water to get dry) and coat with thin coat of silicon to aid the old gasket in sealing to the new different shaped bolts. Let set up a bit then fill and check for leaks. I don't recommend using the silicon if you are installing a new gasket