how much does a toilet flush diaphram cost?

Materials: Syphon, sealing paste, Two wrenches to un-do and re-place the water joint/s. Plastic ones on the syphone and flush pipe hand tight plus a bit more you can use the wrench but go easy.

Don't know ask plumbing shop I've never bought one just replaced the unit.
Depends on type of syphon some ban be fixed in situ others have to remove the syphon in which case you might just as well replace the syphon unit. Ask about in-situ repair syphon.

High level and low level procedure the same.
Turn off the water, bale out the water from the cistern.
Undo the large nut under the cistern that secures the cistern to pan flush tube. Undo the large nut holding the syphon in place remove the syphon. If you have ball type float you may have to remove the float arm to get the syphon out. Pull out the pin that holds the arm to the inlet valve remove the arm.
Now take the syphon out and refit new one

Close coupled: ie: cistern fixed to toilet pan.
Turn off water. Bale out cistern. remove the water feed pipe [have rags and saucepan ready to catch surplus water.] un-do the cistern securing screws at top back of cistern. Un-do the cistern to pan securing bolts. Lift cistern clear undo syphon nut as above.

When getting new syphon for this type ask also for the doughnut sized cistern to pan sealing washer.
New set of bolts and rubber washers. Better than putting rusty bolts back.
Unsure what goes where take a digi picture and you can then see what went where.
If your cistern is the slim line version then tell the plumbing shop so you get the correct syphon.

Nobby
February 2009