Replacing a Groco HF head

When I got the boat there was something wrong with the head(A Groco HF marine toilet). Water would back up into the bowl so there would be about 4 inches of it in there. The previous owner said it had always worked like that and the manual said the flapper valve being dirty could cause that and cleaning it would fix the problem. I figured as long as I was taking it apart I would get a maintenance kit for it and just replace the replaceable parts. Well things did not quite work out as well as I had hoped.

I had prepared for the worst thinking it was going to be a pretty huge mess and did my best to flush the system with plain old water. Luckily for me it had not really been used that much and when it was used it was mostly liquid waste.
This is a picture of the base. The pump is on the right and the bowl is on the left. the black pipe on the left of the pump is the water intake and the bigger black pipe going into the wall is the waste line that goes to the holding tank. The base is the horizontal pipe at the bottom.


The instructions on the maintenance kit from Groco are pretty much the exact same thing you get with the toilet when you buy it. They are pretty vague and leave a lot to be desired on detail. It is really just a single 8.5x11 page front and back with a diagram of the parts and a parts list for the kits. A hint or two about how to proceed would have been nice so that is why I am putting this here so someone else can get a heads up about what to expect. Anyway I decided to start by unscrewing the 3 bolts that hold the pump to the base and let the water drain out. I tried to mop it up as best I could as it came out.


I was sort of suprised that the only water that really came out of it was the water that was in the bowl. I figured the waste line would have something to contribute as well.
This is the base with the pump off. The flapper valve is the black triangular part on top of the base. The joker valve is the part that is still in the waste line. I was wondering if it was holding back the stuff in the waste line but there was nothing in the line to hold back. yay!



Here is the pump after it has been removed. Nothing especially interesting about it and as far as I know it was working fine.







If you go back a few pictures and look at the flapper valve you can see some stuff stuck to it. That stuff turned out to be some kind of silicone. I was confused by that at first until I started looking at the base.

After peeling off the silicone and poking at it a bit you can see that it is corroded very badly. Someone had tried to fix it by caulking it. I guess if you don't mind water potentially sloshing out of your toilet when the boat heels over I guess you could be happy. I was not too happy as no amount of cleaning or replacing was going to get it to work properly. The corrosion was pretty deep into it as well. It may have been possible to grind the brass down several millimeters to make it flat again but I don't have that kind of equipment so it pretty much meant a new base. I wandered off to West Marine figuring that they would not have the base but I knew they had the same Groco HF head that I had. A price check revealed that the price of the base was $100 and would need to be ordered. The new HF was $300. I could probably have gotten the base someplace else cheaper but I am not terribly patient and I already had the thing apart so I bought a new one.

This is what the base that the flapper valve sits on looks like when it is new. A nice smooth surface for the valve to seat on.








I did run into some aggravation while installing the new bowl. You are supposed to put plastic washers on the bolts that hold the bowl to the base. The washers are too big to fit on one of the sides and very tight on another. They fit fine on two sides though. I checked the alignment and futzed with it for quite awhile before I just gave up and snipped a side off the washer and put it on. The nut still kind of ground on the side of the porcelain though. I don't know why they made it so tight of a space. Not like they need to save that room since the bowl expands outward from there.
Here is the offending bit. The washer is wedged in there and the bolt is already on the porcelain. Even getting the nut on was a pretty tight fit. All the washers were wedged pretty tight on the porcelain.
Oh and the bolts for attaching the bronze base to the do not come with the kit so you need to get them to suit whatever you are attaching the head to.






In summary I was much more worried about doing the maintenance kit than it really was. The mess was negligible and once you start taking things apart it is a pretty simple device. One thing I did learn is that it is probably better to take the thing apart first and figure out what is wrong. I have a maintenance kit I can use when I need it but hopefully that will be several years down the road. I have heard that Groco is really good if you call in for support so if you really get stuck you can call them.