Title photo
frugal technology, simple living and guerrilla large-appliance repair
Tue, 15 Dec 2015

I re-rebuilt the Dishmaster faucet again, plus re-did shower valve job

I rebuilt our Dismaster faucet about a week ago, a couple of weeks after a washer-assembly replacement failed to stop it from leaking.

That's because the valve seats were shot. I have never replaced the valve seats before, mostly because I had no idea how to get the old ones out.

The Dishmaster is designed like no other plumbing fixture I've ever worked on. Not that my experience is so vast.

The washers are mounted on plastic assemblies that snap on to the valve stems and turn freely on them. That enables the washers to make a tight-enough seal against the valve seats without grinding when you continue to turn them (unless you turn them a whole lot).

It kind of, sort of mimics the feel of a ceramic-disc faucet while still using a rubber washer against a metal valve seat.

A couple of weeks ago, I pulled the valve stems and replaced those washer assemblies. Not as cheap as regular washers by a long shot, but not a total deal-breaker, pricewise, either.

When that didn't work, I knew I had to figure out how to replace the valve seats.

First of all, I couldn't find the Dismaster M76 model's valve seats at any of my local plumbing or hardware stores. I had to order them. I got them from Casler Hardware, where the prices were good, though the shipping costs were high. Prices were higher [direct from Dishmaster], but I was more confident that Casler would ship quickly, so I chose them for this particular order.

Once you get the valve seats and the all-important Union O-rings that seal the faucet at a critical point, you can read the instructions, or just [see them on the Web].

You remove all of the outside parts of the faucet, then unscrew it from the back at what are called the unions, I believe.

Then you use a hex-key wrench to remove the valve seats from behind instead of the usual way (from in front with a valve-seat wrench). Curiously, the valves seats hold in the bolts that join the front of the faucet to the "unions."

The "kit" from Dishmaster includes two new rubber O-rings to put in the little grooves between the faucet and the unions (which are what screws into the 8-inch-center water-supply pipes).

Once I got the whole thing apart, I found that I had two screens in the line that are designed to trap debris. Curiously -- or maybe not -- the Dishmaster instructions say to discard these screens and not replace them (which is easy to do, as new screens are not included).

And I think it's a good thing, too, because behind the screen on the hot side was a whole lot of crap that was really killing my water pressure.

When I was removing the faucet, I had the water shut off, but after I had the whole thing apart, I had my daughter hold rags over the open water lines (with faucet unions only), and then turned the water supply on a few times to clear the lines and get all that crap out of there. She was reluctant to help due to the possibility that she would be doused with water, but she agreed to do so. She emerged unsoaked.

With the water lines cleared, once I got everything put together, I had a good deal more water pressure out of the faucet, which is connected to some of the oldest galvanized piping in the house and is farthest from the water heater.

I had another problem that was solved by taking the faucet apart. Originally when I removed the cold-side valve stem, the brass part came out, but the plastic part that contains the washer stayed in the valve area. I didn't want to break it into pieces and have a non-working faucet. But with the bulk of the Dishmaster unmoored from its unions, I went from behind and knocked it out with a screwdriver and hammer.

Once I peeled the old union O-rings out of the unions and replaced with the new ones replaced the plastic washer assemblies on both valve stems and pulled the old valve seats from behind with the proper hex wrench (I think it was a 7/32", but don't quote me) and replaced them with the same, taking care to replace the union nuts when doing that, I was ready to put the faucet back together.

Once the valve seats and union nuts were in place, I screwed the front of the faucet onto the unions, where the new O-rings provided a tight, waterproof seal.

Then I reinserted the valve stems, blue on the cold side, red on the hots side, and turned the valves until they were properly seated.

Note: I could have gotten totally new valve stems and plastic nuts, and I probably should, but these seemed perfectly fine and I saved a whole bunch of money because I've seen the valve stems go for up to each.

I got the valve stems back in, then put the rest of the faucet back together, first replacing and connecting the soap tank (which I never use; the faucet stem itself is leaky and I don't really "need" the Dishmaster's core feature; for me it's just a long faucet with nice handles, when they work).

then I put the covers back, and "tuned" the position of the hot and cold handles so the faucet would turn off the flow of water but not turn too hard.

There is always a period of adjustment after rebuilding a Dishmaster. You have to watch for leaks, then unscrew the handles and move them "down" a notch so the faucet turns off tighter in order to stop the leaks. They "settle in" after a week or two, I think.

Then (and for me now) you have a non-leaking Dishmaster faucet with easy-on and -off handles.

Rebuilding a Dishmaster isn't easy, but there are harder plumbing jobs, for sure.

The last time I rebuilt the Dishmaster, maybe a couple of years ago, I said I'd never rebuild it again and instead would buy a whole new one. Of course enough time had passed that I forgot the pain and did it again. This was the first time replacing the valve seats, and they were in bad shape. That part of the job has made the faucet as "like new" as it could be. I could have gotten the "all exterior parts" kit for about to make it look newer, and I could spend maybe on a new spout (which is leaking from the top, even though I did rebuild it a few years ago).

I based my "never again" rebuild pledge on what I thought a new Dishmaster cost, which was about . Now I see that the "street price" of a new Dishmaster is , I got religion on the rebuild and went through with it.

The faucet doesn't look like new. That's because it isn't.

But as a faucet, if not as a soap-dispensing aid, it works very well. And that's all I can ask.

I also rebuilt my shower valves at this same time. It's a standard Price Pfister fixture, and I did new valve stems and valve seats. It's a job I've done quite a few times before (we also have a Price Pfister tub fixture), and it went well except for one thing.

I like to use a "hot" stem that turns the opposite way from the "cold" to make it easier to visualize when turning on and off and adjusting the temperature, and this new "hot" stem became VERY hard to turn after a few days.

I think the packing inside the stem somehow got loose and gummed up the works.

I have a huge stock of used valve stems, and I found an original Price Pfister stem, greased it, replaced the washer and washer screw, and replaced the "new" stem with the old one. It's been working great since then.


Images from Dishmaster are, from top, torque-free valve-stem ends and washers, valve seats and union O-rings, hot water stem and cold water stem -- all for the M76 model faucet.