Toilet Maintenance, Groco Model K

[Christian Williams]

...

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.

......

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.



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?



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]

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]

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

 

[footrope]

Good story. I would like to add some kudos to Groco also. I have an elderly Groco Model HF toilet, the one with the vertical pump. It is not the original one that was in the boat. It was acting strangely when being pumped, not clearing the bowl. On the HF you don't take the bowl off for any pump related rebuilds or routine maintenance. The pump is a separate assembly next to the bowl. I took the pump off, expecting the shaft to be separated from the plunger piece, but it was intact. The flapper valve at the bottom of the pump tube may have been hung up. I lubed the pump body with silicone grease and reassembled it (no spare!). While tightening the screws that attach the pump to the outlet hose, the brittle plastic flange cracked through to the pump tube and it leaked slowly. It was Saturday night at a popular San Juan Islands anchorage. We were planning to enter Canada the next morning.

We back-tracked to a spot with better cell coverage (Blind Bay, Shaw Island) the next day, spent the night, and Monday morning searched online for replacement parts and assemblies for the HF. The HF is a very popular toilet! We then contacted several marine supply places in Friday Harbor and Anacortes. North Harbor Diesel in Anacortes could get me the whole HF pump assembly, plus a few more supporting parts in a kit, the next day. No shipping cost since they get a daily truck from Fisheries in Seattle. So, we got a slip at Cap Sante in Anacortes for a couple nights and made the easy fix. The cost was about $400 for the parts, plus 2 nights guest moorage, and 4 lost days in Canada. We still made it to the Southern Gulf Islands for 6 nights - had a great time.

A thank you to Groco for making such fine fixtures, and for supporting then for so many years. And a big shout out to the helpful folks at North Harbor Diesel for the convenience and connections that got the correct part overnight.

 

[Bolo]

I don't have a Groco model K, HF or any other letters but now after reading this thread I think I have marine toilet envy.

 

[Pete the Cat]

I don't have a Groco model K, HF or any other letters but now after reading this thread I think I have marine toilet envy.

Good story. I would like to add some kudos to Groco also. I have an elderly Groco Model HF toilet, the one with the vertical pump. It is not the original one that was in the boat. It was acting strangely when being pumped, not clearing the bowl. On the HF you don't take the bowl off for any pump related rebuilds or routine maintenance. The pump is a separate assembly next to the bowl. I took the pump off, expecting the shaft to be separated from the plunger piece, but it was intact. The flapper valve at the bottom of the pump tube may have been hung up. I lubed the pump body with silicone grease and reassembled it (no spare!). While tightening the screws that attach the pump to the outlet hose, the brittle plastic flange cracked through to the pump tube and it leaked slowly. It was Saturday night at a popular San Juan Islands anchorage. We were planning to enter Canada the next morning.

We back-tracked to a spot with better cell coverage (Blind Bay, Shaw Island) the next day, spent the night, and Monday morning searched online for replacement parts and assemblies for the HF. The HF is a very popular toilet! We then contacted several marine supply places in Friday Harbor and Anacortes. North Harbor Diesel in Anacortes could get me the whole HF pump assembly, plus a few more supporting parts in a kit, the next day. No shipping cost since they get a daily truck from Fisheries in Seattle. So, we got a slip at Cap Sante in Anacortes for a couple nights and made the easy fix. The cost was about $400 for the parts, plus 2 nights guest moorage, and 4 lost days in Canada. We still made it to the Southern Gulf Islands for 6 nights - had a great time.

A thank you to Groco for making such fine fixtures, and for supporting then for so many years. And a big shout out to the helpful folks at North Harbor Diesel for the convenience and connections that got the correct part overnight.

I owned a Groco model HF on my Tartan 37 for 30 years and rebuilt it three times in that period. I finally tossed it in the dumpster a month ago and am very happy about having it out of my life--I did not wish it on any other boater. It always leaked fresh water no matter how many times I took it apart and reassembled it. The engineering in it was ridiculously complicated compared to more modern heads, it was held together with self tapping screws into PLASTIC!!! and the springs and valves had to be placed EXACTLY in the proper clock orientation--not specified in the instructions no matter how you squint to see the tiny diagrams, you only learn this by doing it wrong and doing it over several times--I am a decent amateur mechanic who has rebuilt several diesels from junk to running --and am a fanatic about flushing with fresh water, lubricating and following the "directions" included with the expensive Groco rebuild kits I bought and installed. I actually think I spent more hours rebuilding that head than rebuilding the Westerbeke diesel over the years.
I recently replaced it with a $175 Swedish head that is the picture of simplicity in its design internally and externally. For the first time there is not water running down my fingers with every push of the handle. The operating instructions are simple and and intuitive. The basic repair kit for the Groco would have cost nearly as much as this whole head. If it breaks, I will probably just buy a new unit--because I vow never to spend another day on the dock with head parts, but the engineering looks very simple and its construction has actual machine screws and far fewer springs and flaps to foul. Flushes faster and more completely.
The previous owner installed a Jabsco electric head on my Ericson 32--200 and I recently rebuilt it (nothing was wrong, I just wanted to make sure it was in good shape prior to a cruise) and it is marvelously well-engineered and simple to service by comparison to the Groco HF. In my 40 years of boat ownership, I would rate my Groco HF head as the most poorly conceived and constructed piece of equipment I have had on a boat--though the cooling system on my old Westerbeke was a close second.
Just another viewpoint. I understand they have excellent customer service. Perhaps they really need to have that.

 

[nquigley]

So, to summarize … not a fan.

 

[Christian Williams]

Note that the Model K is all bronze and porcelain, no plastic, indestructible and long-lived.

 

[Saverio]

View attachment 44329...View attachment 44405

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.

...View attachment 44331...View attachment 44332

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.

View attachment 44333

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?

View attachment 44334

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.

beautiful photo report

 

[Christian Williams]

Why thank you. But I insist the beauty is in the toilet, and none of my doing. I will chance photo recapitulation:



How it gleams and shines! How receptive it lies with open arms, so to speak, how ready to please, how excellent in its knowledge of self and accommodation to service! We can all take a lesson, from Kanye West to Liz Truss*, from the Model K. Ready when needed! Speaks only when asked! No plastic!

It is odd to get defensive about a toilet, but one must defend one's own.

*Truss resigned as British PM in 2022 after only 45 days in office, a record failure of "gleam and shine." Kanye West is just a jerk.

 

[Bolo]

How it gleams and shines! How receptive it lies with open arms, so to speak, how ready to please, how excellent in its knowledge of self and accommodation to service! We can all take a lesson, from Kanye West to Liz Truss, from the Model K. Ready when needed! Speaks only when asked! No plastic!

The first time I ever read anything so “poetic”… about a commode.