630-0030 Flush Valve Seal Gasket

Homeowners dealing with a toilet that keeps refilling or seems to leak slowly into the bowl may want to look at the flush valve seal before replacing larger parts. This silicone gasket is made for Mansfield 210 and 211 tower-style flush valves, plus select Model 160 tanks that use the 211 valve. The four-pack gives you replacement seals and spares for later maintenance. It’s a great fit if the existing seal is worn, aged, or deformed and you’ve confirmed the valve model, it isn’t a universal toilet-tank gasket.

Best use cases

A worn seal can let water pass between the flush valve tower and the tank opening, which may lead to a running toilet, slow leaks, repeated refilling, or flushing that feels difficult. Replacing the seal is a focused maintenance step: for example, if the toilet refills after a flush even when nobody has used it, removing the tower and replacing its gasket may address the seal as the source of the problem. It won’t fix unrelated issues elsewhere in the toilet, so identifying the valve first matters.

This replacement is intended for 630-0030 seals and related Mansfield 0030 flush valve service applications. The stated fit covers Mansfield 210 and 211 tower-style valves, and select Model 160 tanks only when they use a 211 flush valve. Better avoided if your toilet uses a different valve design or you can’t identify the existing model, the listed fit is specific, not a claim of broad compatibility.

Product specs

• Part number: 630-0030
• Material: Silicone
• Package: 4 flush valve seals
• Compatibility: Mansfield 210/211 tower-style flush valves and select Model 160 tanks using a 211 valve

The silicone is described as flexible and intended to resist hardening, deformation, and wear during regular tank use. From the way it is set up, installation means removing the old seal, seating the replacement in the groove, then reinstalling the flush valve tower. The four seals can be useful when you want spares on hand, though the pack does not include a stated valve tower or other repair components.

Where it shines

This part keeps the repair narrow: rather than replacing a larger assembly when the seal itself is worn, you can swap the gasket and retain the existing tower. That approach makes sense for routine maintenance when the toilet’s symptoms point to a poor seal and the valve matches the stated models. If the tower is damaged or the cause of repeated refilling is elsewhere, a seal-only replacement may not solve the underlying problem.

The practical first step is to compare the existing flush valve with the compatibility details before opening the tank. That distinction is especially important for Model 160 tanks, since the stated fit applies only to those using a 211 flush valve. A correct match gives the new gasket a clear job: restoring the seal at the tower-to-tank opening.

Final verdict

Choose this 630-0030 four-pack for a targeted seal replacement when your toilet has a compatible Mansfield 210 or 211 tower-style flush valve and the old gasket appears worn. It offers a simple alternative to replacing more of the flush assembly when the gasket is the likely culprit, with spare seals included for future maintenance. Skip it if your valve model doesn’t match, or if the toilet’s problem points to a damaged tower or another part rather than the seal.