Isolate the water supply. Flush the toilet and soak up the last of the water. To make this repair youll need to disconnect the tank from the pan. Unscrew the water supply coupling nut from the bottom of the tank. Next unscrew the bolts holding the toilet tank to the bowl by loosening the nuts from below. An Enfield Boiler Repair plumber carries special tools. Take the chain from the handle. Take off the tank, then carefully place it on an old large bundle of rags. Remove the spud washer and its nut from the bottom of the flush valve using a spud wrench or big pliers. Place the new flush valve in the hole and ensure the top of the overflow pipe is at least an inch below the top level line of the tank opening where the handle is. Place the valve flapper below the handle lever arm and secure it to the tank from beneath with the correct nut. Tighten the nut. Over tightening can cause the tank to crack. Put the new spud washer over the spud nut with the smallest side downwards. Enfield Boiler Repairs carry out this type of job. Now thread a rubberised washer onto each bolt and insert them in their. Then, thread a brass washer and hexagonal nut on the bolts, hand tight, carefully lower the tank over the bowl and let it down so the spud washer fits over the water inlet in the bowl and the tank bolts fit through the holes in the bowl flange. Fix the tank and bowl together. Connect the water. Fit the chain clip at the handle and allow for some slackness in the chain. Leave some room for adjusting on the chain. Fit the overflow pipe. Turn on the water supply at the stop valve and test the flush.