The washers are not your problem it is the brass seats that are worn. The seat is the mate for the washer which sits in the fixture. Seats become scuffed and as a result damage washers. Go to a plumbing supply house(not box store) and explain your issue, they may be able to supply you with the proper tool and seats.It is iffy if the seats can be replaced.
Honestly,I would just replace the sink and fixture, it may cheaper and a whole lot easier. Besides those fixtures have been illegal for some time, scolding from hot water a major problem.

Thanks jonnyp...I was hoping it was washers, but I will try replacing the seats; a new sink is NOT an option. From looking at some repair sites, it seems valve seats are still made, or I can try dressing it. If all else fails there seems to be a thing called a seat sleeve which can be inserted.

If I wanted a new sink, I'd have bought a new house. :)

If you are able to get a year out of it, I might suggest to just keep replacing those seat washers and call it a day. (They were probably flat washers.)

The trouble with working with something that old is that the fixture can fall apart from corrosion when you work on it (probably not likely with the seat, but you never know). I just worked on the identical sink and one of the bonnets (escutcheons) disintegrated at the threading during removal. Temp fix was to reinstall it by packing it with plumbers putty and sticking it on, which gave the owners time to make their selection on a new set-up.

If you do want to take a stab at replacing the seats, buy or borrow a seat wrench (forget trying to dress the one you have.) Then unscrew the seat (counter-clockwise) and take it to an old-fashioned hardware store to match it. You can replace with stainless, but make sure otherwise it's not only the same threading, but also has the same profile (height-wise, etc.)

One final note: Before removing a seat, be sure to first locate your old-fashioned hardware store that has a good assortment.

Good luck with it.

This post was edited by homebound on Fri, Dec 28, 12 at 19:42

QUOTE:"Besides those fixtures have been illegal for some time"

WRONG- there is absolutely nothing in the codes that would prevent you from continuing to use those faucets.

While your problem could be resulting from bad seats it is more likely that your premature washer failure is resulting from an incorrect installation procedure.

As the washers wear the stems turn futher and further in until they are in tight contact with the seat to shut the water off.

When you pull a stem to change the washer you have to make sure the stem is turned to the "full open" position before you reinstall the stem and bonnet. If you fail to turn the stem to the open position, after you replace the washer and reinstall the seat, the bonnet will pull the stem into the exact same position where it was with a defective washer. That will result in instantly compressing the new washer until it is the same as the defective one you pulled out. If you will turn the stem to the full open position the stem will not make any contact with the seat until after you have properly tightened the bonnet and then turned the stem in to the closed position.

lazypup--you know, whether the tap is full on when I remove the faucet is something I never checked! I will take a look at that when I buy some more washers this week--it sucks that a variety pack has only about four which are the size you need, and the other fifty are so weird that they probably will never fit anything you own. :)

And with mixing faucets, isn't it that only shower or bath ones should have the pressure balancing? Never heard of such a thing for a sink! Personally, I don't have my water heater set to incinerate because gas is too expensive for that. :) Mine is set between low and the vacation setting, which is perfectly fine for dishes and washing me.