Conversion of Groco HF to Superflush, or just replace the whole thing?

[Sea Glass]

Hi!

I've just purchased a Vineyard Vixen 29 - a good old boat that's had a bit of deferred maintenance. One of the first orders of business is to address the sanitation system. It's all rather "sweet" (if you get my/its drift), and my guess is that all components are at least 20 years old. Hoses are discolored, tank has ooze on it, the whole boat smells weird, etc. So I'm about to tackle my first complete marine plumbing overhaul.

I purchased Peggie Hall's book, which has already proved invaluable in planning my overall attack. But I'm sure to still have many specific questions along the way, so I thank you all in advance for your expertise!

The boat has a Groco HF head, and I learned from this forum that Raritan offers a Superflush conversion kit. Looks like that would leave me with just the original bowl and lid, which I don't have much emotional attachment to keep. If I choose to just purchase an entire new Superflush head, is the base identical to the conversion kit? i.e., will the holes match existing toilets as claimed in the conversion kit? The Superflush doesn't mention it

Attached are a few "before" photos showing how things stand today...I'm still mapping out a plan, and trying to figure out how everything works now.

[peghall]

Groco bowls are a bit unique...they don't fit any other toilet base. So a SuperFlush conversion won't work. I think the SuperFlush mounting bolt pattern is a match, but it's no big deal if it isnt 'cuz I've always recommended filling and redrilling bolt holes...that guarantees the new boltswill get get a good "bite" in the fiberglass, which they may not in the existing holes.


Boatersland has it with what I'm pretty sure is the small "marine" bowl for $360. Boatersland Raritan PH SuperFlush Toilet

Defender has it with "household size bowl for $405 Raritan PH SuperFlush Manual Marine Toilet - Household | Defender Marine


--Peggie

[Sea Glass]

Thanks, Peggie- this is helpful! I will just pick up a new compact unit. I see Defender has those on sale right now as well.

While we're at it, I have another question for you. Right now my boat has its head intake and sink drain plumbed as two separate seacocks in the STB bow, under the vee berth. My head is on PORT, and that makes for two runs of 5-6' hose across the boat under the v-berth.

After reading your suggestions, I'd like to reduce to one seacock combining both head intake and sink drain. I can lose one hole in the boat and make purging with fresh water and winterization more convenient.

But why did they put those seacocks way over on starboard? Any reason they located those two seacocks on the opposite side of the boat, rather than directly under the sink in the head? I could easily fit one in an accessible location beneath the water line and directly under the sink. But not sure if I'm missing something...

[Bowdrie]

Originally Posted by Sea Glass

I'd like to reduce to one seacock combining both head intake and sink drain.

All well and good until the head inlet starts sucking bits of food/coffee grounds, and greasy dishwater out of the sink drain.
No thanks.

[Sea Glass]

Hi Bowdrie-

Thanks for the comment. I should've been more clear that my idea is that this would be only for the head sink (that will be used rarely, and only for hand washing). I have a separate galley sink with its own drain.

[Bowdrie]

Originally Posted by Sea Glass

Hi Bowdrie-
Thanks for the comment.

Tis Ok, I'm a bit chagrined that I first thought of the galley sink instead of the head sink.
Carry on, good luck with the head project.

[peghall]

Both the toilet and the sink/sink drain thru-hull have to be on the same side of the keel for this modification to work. If that's true, rerouting the toilet intake line to tee into the head sink drain line is easy. And from what you write here, it appears that the toilet and and the head sink are on the same side of the keel, but the head sink drain thru-hull isn't. (The head intake thru-hull location is irrelevant to this discussion 'cuz you won't be using it).

If the boat is out of the water for the winter, this would be a great time to move the head sink drain thru-hull and close off the head intake thru-hull unless you have another use for it (washdown pump maybe?)

Give me a shout via PM or email and I'll help you work out the details.

--Peggie

[peghall]

I learned about teeing toilet intake line into the HEAD sink drain line (not many coffee grounds, food bits or greasy dishwater go down most head sinks)from a Tartan owner in the mid-90s...that's how Tartan was plumbing their head intake line then. I fell in love with the idea and have been recommending it ever since as a safe way to provide a fresh water rinse for head plumbing. I have yet to hear of it causing problems to anyone.


--Peggie

[peghall]

Your comment was actually useful 'cuz it prodded me to remember that some smaller boats only have one sink--a galley sink...and to verify that we're talking about a head sink when I recommend that modification to the toilet intake.


--Peggie

[CindyP]

Originally Posted by peghall

Groco bowls are a bit unique...they don't fit any other toilet base. So a SuperFlush conversion won't work. I think the SuperFlush mounting bolt pattern is a match, but it's no big deal if it isnt 'cuz I've always recommended filling and redrilling bolt holes...that guarantees the new boltswill get get a good "bite" in the fiberglass, which they may not in the existing holes.


Boatersland has it with what I'm pretty sure is the small "marine" bowl for $360. Boatersland Raritan PH SuperFlush Toilet

Defender has it with "household size bowl for $405 Raritan PH SuperFlush Manual Marine Toilet - Household | Defender Marine


--Peggie

We are planning to replace our old Grocco HF with the Raritan PH Superflush. I don't think the bolt holes will align from looking at the product info sheets. Question:. Without being able to reach underneath to put a nut on the new bolts, how is the toilet held down adequately?

[peghall]

Toilet mounting bolts are "lag bolts"...there are no nuts on them. Just back them out.


Bolt diameters can vary an almost imperceptible amount brand to brand or even new vs old for the same brand. So even if one or two of the existing bolt holes are a match for the Raritan toilet, I strongly recommend that you fill and retap them to insure a tight fit, 'cuz the last thing you need is a wobbly toilet!


--Peggie