I'm tired of Groco repair kits $$$$ Are you?

Oct 22, 2014
352
Pearson P303 #221 RockPort Maine
No matter what I do my Groco system fails to stop raw water from filling the bowl with raw-water only to resort to shutting the seacock after usage. Or, just maybe I don't know how a system like this works...LOL Anyway, I have solved the problem and works for me and others too. I have taken the output of the Groco pump leading to the bowl that fills the bowl to flush and installed a simple PVC Open/Close valve so after your done flushing close the valve. No need to close the seacock and no more BUYING KITS! I have used this the last two seasons and IT WORKS! I have saved hundreds of dollars already. Capt. Rob
grocko.png
 

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Feb 10, 2004
3,917
Hunter 40.5 Warwick, RI
I have a Groco (doesn't almost everyone?) and I have installed rebuild kits many times over the years. If after a new rebuilt kit is installed you almost immediately have the raw water inflow problem, I would suspect one of two things. Either the pump body or some part that has not been replaced has some fault or the toilet is so far below the water line that the incoming pressure is simply too high for the inlet valves to stop.
Peggie claims that if you insist on keeping the Groco, the smart money is to just buy a complete pump.
 
Feb 26, 2004
22,759
Catalina 34 224 Maple Bay, BC, Canada
or the toilet is so far below the water line that the incoming pressure is simply too high for the inlet valves to stop.
Given the OP's diagram, if his head is below the waterline (and many are) then his mistake is not putting a vented loop in that line, rather than a shutoff valve.
The vented loop, BTW, is in the installation manual. For every single manual marine toilet. RTFM!
 
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Feb 10, 2004
3,917
Hunter 40.5 Warwick, RI
Given the OP's diagram, if his head is below the waterline (and many are) then his mistake is not putting a vented loop in that line, rather than a shutoff valve.
The vented loop, BTW, is in the installation manual. For every single manual marine toilet. RTFM!
Ha! I missed that Stu! You are completely correct. If there is a vented loop that is actually functional, then there would be no seawater pressure on the inlet valve.
 
Dec 2, 1997
8,708
- - LIttle Rock
Stu nailed the problem...but believe or not there's no mention of a vented loop in the intake in the Groco HF installation instructions. But it's in the installation instructions for every other manual toilet...see the drawing on p.3 of the Jabsco manual toilet owners manual Jabsco Manual Twist & Lock owners manual ...Figure 2 on p. 5 in the Raritan PHII owners manual PH II Owner’s Manual ...and Figure 5 on page 5 of the Raritan PH SuperFlush (newest version of the PHII) Raritan SuperFlush Owners Manual As you'll see, it's in the same place in all of 'em: between the pump and the bowl (if installed between the thru-hull and the pump it interferes with the pump's ability to prime). It needs to be at least 6-8" above waterline AT MAX HEEL, not just when the boat's at rest..which puts it about 2-3' above the bowl on most sailboats. That requires replacing the short piece of hose that Groco used to connect the pump to the bowl with two lengths of 3/4" sanitation hose long enough to put the loop where it has to go (see attached photo for the most common location...the smaller loop is the intake...a discharge vented loop is only needed if you flush directly overboard when at sea beyond 3 miles).

But I wonder if you DO know how your toilet works...'cuz it already has a built-in "open/close" valve. At the bottom of your drawing, you'll see a little lever on side of the pump...that's the wet/dry control (aka "dry/flush" control on some toilets). It only allows flush water to come in when it's in the "wet" or "flush" position...blocks the flow of flush water when in the "dry" position. It can fail with age, but since you didn't mention that water comes in no matter which position it's in, I doubt that's the problem. It is NOT a substitute for the vented loop because people can accidentally leave it in the wet mode, but it does prevent water from filling up the bowl while it's in the dry mode.

Rob, you've been on sbo.com for nearly 5 years... You've posted nearly 400 times on other topics, read a lot of my posts, even liked a few. So WHY didn't you ask for help with this problem BEFORE you (and others who apparently don't know how their toilets work either) spent a bunch of money for kits and a valve none of you needed???? I'd have been glad to help you solve the problem the right way.
--Peggie
 

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Oct 22, 2014
352
Pearson P303 #221 RockPort Maine
Rob, you've been on sbo.com for nearly 5 years... You've posted nearly 400 times on other topics, read a lot of my posts, even liked a few. So WHY didn't you ask for help with this problem BEFORE you (and others who apparently don't know how their toilets work either) spent a bunch of money for kits and a valve none of you needed???? I'd have been glad to help you solve the problem the right way.
--Peggie

Thanks, Peggie and yes I do know how the pump works, however, all that I've read on do this do that, was just eating up my time to enjoy boating. I have installed the two loops that you have but can't take them high enough in the space allowed. I do not want loops of hoses climbing up my headwalls. I've tried it all and this is the only thing that guarantees it won't fill the bowl regardless as to any sailing conditions. After putting in a new pump and it failed too within 2 weeks. flip the lever up and flush it down, flip it down and empty the bowl. close the lid and shut the new valve, DONE! You don't have to worry about what position the lever is in, vent hoses and where do I put them, and in some boats, they are in plain view. IMO.
Peggie, Your right should have asked for help! My Bad. Best regards, Capt Rob.
:deadhorse:

This is my installation to date. above water level. In the current condition with it being brand new... It leaks raw water into the bowl.
 

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Jan 7, 2011
4,723
Oday 322 East Chicago, IN
Rob, you've been on sbo.com for nearly 5 years... You've posted nearly 400 times on other topics, read a lot of my posts, even liked a few. So WHY didn't you ask for help with this problem BEFORE you (and others who apparently don't know how their toilets work either) spent a bunch of money for kits and a valve none of you needed???? I'd have been glad to help you solve the problem the right way.
--Peggie

Thanks, Peggie and yes I do know how the pump works, however, all that I've read on do this do that, was just eating up my time to enjoy boating. I have installed the two loops that you have but can't take them high enough in the space allowed. I do not want loops of hoses climbing up my headwalls. I've tried it all and this is the only thing that guarantees it won't fill the bowl regardless as to any sailing conditions. After putting in a new pump and it failed too within 2 weeks. flip the lever up and flush it down, flip it down and empty the bowl. close the lid and shut the new valve, DONE! You don't have to worry about what position the lever is in, vent hoses and where do I put them, and in some boats, they are in plain view. IMO.
Peggie, Your right should have asked for help! My Bad. Best regards, Capt Rob.
:deadhorse:

This is my installation to date. above water level. In the current condition with it being brand new... It leaks raw water into the bowl.
Buy a Raritan PHII.

I had a Jabsco on my last boat. Had to rebuild it all the time...water backfilled into the head.

Current boat has a Raritan PHII, not sure how old it is (boat is 10 years older than my first bloat)...but I haven’t had any problems with this one. Finally rebuilt the pump and joker valve this spring...works even better.

Bite the bullet and get it over with ;-)

Greg
 
Oct 22, 2014
352
Pearson P303 #221 RockPort Maine
current instalation.jpg
View attachment 166322 View attachment 166322
Buy a Raritan PHII.

I had a Jabsco on my last boat. Had to rebuild it all the time...water backfilled into the head.

Current boat has a Raritan PHII, not sure how old it is (boat is 10 years older than my first bloat)...but I haven’t had any problems with this one. Finally rebuilt the pump and joker valve this spring...works even better.

Bite the bullet and get it over with ;-)

Greg
Thanks, Greg! If and when I do change out the system I definitely will look at your Raritan PHII system. Did you have to install any loop's in your system? I currently have one as shown in the picture about 3feet underneath the lav sink. There is no room for an input loop without going outside lavatory sink cab and up the wall. This is not an option for me.
 
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Dec 2, 1997
8,708
- - LIttle Rock
An intake vented loop is needed on all sea water toilets, manual or electric, that's installed below waterline.
There is no room for an input loop without going outside lavatory sink cab and up the wall. This is not an option for me.
You can't run the toilet intake line straight up behind the toilet to put it on the bulkhead behind the toilet as shown in the photo I posted in my previous reply???
--Peggie
 
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Oct 22, 2014
352
Pearson P303 #221 RockPort Maine
An intake vented loop is needed on all sea water toilets, manual or electric, that's installed below waterline.
You can't run the toilet intake line straight up behind the toilet to put it on the bulkhead behind the toilet as shown in the photo I posted in my previous reply???
--Peggie
Peggie thanks for the info. However, mine is installed above the waterline.. does the loop still apply?? see Fig 4 drawing as a referance. Thanks, Capt. Rob
 
Dec 2, 1997
8,708
- - LIttle Rock
As long as it's installed entirely above waterline and remains entirely above waterline even at max heel, no. But there's no way it could be entirely above waterline even at max heel if sea water was flooding your bowl when the intake seacock was open.
-Peggie
 
Oct 22, 2014
352
Pearson P303 #221 RockPort Maine
As long as it's installed entirely above waterline and remains entirely above waterline even at max heel, no. But there's no way it could be entirely above waterline even at max heel if sea water was flooding your bowl when the intake seacock was open.
-Peggie
Thanks for your reply. The seacock inlet is 2 feet below the waterline while the bowl is 6 inches above the waterline. In a resting state (at the dock) the bowl fils up in about 15 to 30 minutes. At sea under motor no healing 5 min. Under sail with healing 10 min. However, with the new valve closed it never fils up. I tested by moving pump lever down for closed and it still fills. So I felt the next best thing was to add my new shutoff valve. The pump systems new and had a very experienced marine person look at it and he basically said, It can't be but, it was. So I don't know what to say here.
One thing I will look at when I dive below is the position of the water- scooper-seacock or Clamshell threw hull. Maybe it's installed backward. Capt. Rob
 
Dec 2, 1997
8,708
- - LIttle Rock
If the the wet/dry lever doesn't block the flow of flush water when in the "dry" mode, the lever isn't moving the cam to block it.
A vented loop's primary function is to break a siphon... Priming a toilet pump can start a siphon. The loop offers the added protection of creating a "hill" in a line that's too high for rising water to climb over. It also provides a fail-safe that neither a properly working wet/dry "valve" nor your valve can: keeps water out of the bowl if valves are left open...which can happen 'cuz humans are fallible. If they're lucky, people are aboard to notice that shoes are afloat in the cabin. (I remember crewing in club race and needing the use head in the nick of time to close the wet/dry valve before the bowl overflowed...the people on the Tartan in the next slip weren't quite that lucky...they were manning mops when we came in...one of their kids had left the toilet in the wet mode.) But more than one boat has sunk its slip 'cuz tired people got a little careless when closing up the boat or a guest needed to use it "one last time..."

Install the d'd loop! :)

--Peggie
 
Oct 22, 2014
352
Pearson P303 #221 RockPort Maine
Thanks, Peggie. I will start installing an intake loop and give it a try this afternoon and let you know later on this evening how it worked. Thanks again for your advice. Capt. Rob
 
Dec 2, 1997
8,708
- - LIttle Rock
It'll be easy to do and work just fine if you install it between the pump and the bowl and high enough directly above the toilet. Be sure to get an air valve for it...it's a li'l doodad that threads into the nipple on the top of the loop...needed to prevent any squirting.

--Peggie
 

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Jan 7, 2011
4,723
Oday 322 East Chicago, IN
View attachment 166323 View attachment 166322 View attachment 166322
Thanks, Greg! If and when I do change out the system I definitely will look at your Raritan PHII system. Did you have to install any loop's in your system? I currently have one as shown in the picture about 3feet underneath the lav sink. There is no room for an input loop without going outside lavatory sink cab and up the wall. This is not an option for me.
I do not have any loops in my system. I don’t have overboard discharge, so don’t need it on the discharge hose. I guess I should have it on the fresh water line as Peggy and others indicate, but I do not currently have one.

Greg
 
Dec 2, 1997
8,708
- - LIttle Rock
. I guess I should have it on the fresh water line as Peggy and others indicate, but I do not currently have one.
Only raw water toilets installed below waterline need loops...toilets that use pressurized fresh water from the boat's fresh water plumbing do not.
--Peggie