Toilet Maintenance, Groco Model K

Christian Williams

E381 - Los Angeles
Senior Moderator
Blogs Author
Model K toilet IMG_7740.jpg...head groco.JPG

I'm an admirer of the Groco all-bronze Model K marine head. It pumps easy and with gusto, and the seat is nearly full sized, which you can't say about many boat heads. It is porcelain and heavy bronze, no plastic at all. It does have detractors, who experience difficulty and failure with the full rebuild kit. New Model Ks are still available to buy, apparently. I saw one for sale for $2500.

Mine has functioned without complaint or leak now for 10,000 nm. It had developed a minor personality trait which didn't bother me a bit, but tended to cast shadows upon the faces of guests emerging from the head compartment.

"How was it? The head instructions make sense?"

And they would nod, step over to the sink, and throw up. But--why?

True, upon flushing, the bowl did lately send up a small bright-colored squirt into the face of any observer, and had for a couple of years. I learned to duck, or close the lid. Just didn't bother me. Did some mansplaining and put off the fix. It was really a small squirt.

...toilet flapper MG_7716.jpg...spring flapper toilet IMG_7718.jpg

But, OK. The flapper spring was broken. That spring returns the visible flapper valve to closed, prevents squirt-back, and had corroded off years ago. I ordered the part. Groco has exploded views of the Model K on line, with good customer service by telephone.

toilet base no bowl MG_7720.jpg

The bowl comes off with four bronze machine screws, revealing its gasket and the home of the flapper, which pries out easily.

Naturally, I changed the joker valve while in there. Took an hour, and when reassembled the toilet didn't work. What?

Itoilet joker valve old and new MG_7711.jpg

Internet troubleshooting took me down the rabbit hole of Model K-haters, conflicting opinions, composting advocates, Raritan lovers and other proselytizing poopers, all of them dodging return fire from Peggy Hall, who's everywhere on the topic.

But when it comes to the Model K, Patrick at Groco knows all, and answers the phone. That joker valve--it's finicky. If the toilet won't pump out, it's installed wrong. Rotate a few degrees until an orientation is discovered that allows it to work to prevent backflow of air, which if it happens defeats the pump-out system.

Three hours later and the job is done. It really is a good marine toilet. One doesn't get to say that out loud enough.

The former owner of my boat was a good maintainer, and I have followed his lead with fresh water rise, Odor-los and timely evacuation of the holding tank, and periodic addition of vegetable oil to lube the intestines designed to deal with our own.

There's at least one video tutorial walking through the full rebuild process for the Model K. It's not something I'm looking forward to if it becomes necessary.

Listed on Thelonious Blog here.
 

MaineCapeSailor

Junior Member
I am a 14 year Model K owner and have had no problems with it other than the bolt holding the spring coming loose from the rubber flapper as described by Christian.

One problem I finally resolved was how to align the bolts holding the bowl with the base and gasket when reinstalling - the trick I now use is to first pre-install and align the gasket on the bowl with shorter bolts.

Larry Clough
Bella Luna, 2016 E-32 Maine
 

Tin Kicker

Sustaining Member
Moderator
It had developed a minor personality trait which didn't bother me a bit, but tended to cast shadows upon the faces of guests emerging from the head compartment.

"How was it? The head instructions make sense?"

And they would nod, step over to the sink, and throw up. But--why?

True, upon flushing, the bowl did lately send up a small bright-colored squirt into the face of any observer, and had for a couple of years.
EEWWW !!!

Depending on what your views were on the visitor, this could be a useful feature.
Or not.

LOL
 
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