Can't Prime Head

Aug 4, 2015
41
Catalina 30 Gibralter Boat Yard
Good day all!

I have a 1977 Catalina 30. I recently had to replace a cracked fitting on the head. I can now flush without waste spraying onto the cabin sole. My issue is the clean water inlet is not bringing water into the bowl. My questions are as follows. A: where does the clean water come from (fresh water tank, lake water)? B: is there a way to prime the pump?

Any help would be greatly appreciated.
 
Dec 2, 1997
8,708
- - LIttle Rock
If it's a manual toilet (not electric), pumping it in the "wet" mode pulls in lake water. That requires the flush water intake line to be connected to a below waterline thru-hull. So make sure the seacock on that thru-hull is open and that the wet/dry lever or knob on the toilet is in the "wet" mode. If that doesn't solve the problem, I'll need a bit more information: starting make/model/approx age of the toilet so I can send you a link to the owners manual for it.

--Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein
 
Aug 4, 2015
41
Catalina 30 Gibralter Boat Yard
Thanks Peggie.

I read a link a bit ago indicating the inlet may tee off of the drain for the sink in the head. Ill have to follow the pipes and see if that is accurate. If that is the case then the seacock must be open as the sink drains fine.
 
Dec 2, 1997
8,708
- - LIttle Rock
On your boat, a toilet teed into the head sink drain line would be a PO (previous owner) modification--one that I highly recommend btw...but yes the head sink drain seacock would have to be open. Which, if your sink drains ok, it must be. So I doubt if that mod was done on your boat.
Depending on the make/model/age of your toilet, if making sure the toilet intake thru-hull is open and the toilet is in the wet mode doesn't solve your problem, it MIGHT be time for to replace the toilet pump. If that turns out to be case, there's something else worth considering: replacing the whole system with an MSD portapotty.
On any boat much smaller than about 28', a self-contained system—an "MSD" portapotty-- makes a lot of sense. The "MSD" designation in the model name/number means it has fittings for a pumpout line and vent line, and is designed to be permanently installed (actually just sturdier brackets than portables, so you could still take it off the boat if you absolutely have to), which means that although it's still called a PORTApotty, you don't have to carry anything off the boat to empty it.
A 5-6 gallon model holds 50-60 flushes...you'd need at least a 30 gal tank to hold that many from a manual marine toilet. No plumbing needed except a vent line and pumpout hose--so no new holes in the boat...and -0- maintenance needed except for rinsing out the tank--which you can do with a bucket while it's being pumped out. Total cost including the pumpout hose and vent line is about $200--a fraction of what you'd spend for toilet, tank and all the related plumbing needed. And the best part is, you have all the advantages of a toilet and holding tank without giving up a single square foot of storage space.
Check out the Thetford 550P MSD and the Dometic/SeaLand 975MSD Sanipottie

Just a suggestion...
--Peggie
 
Aug 4, 2015
41
Catalina 30 Gibralter Boat Yard
I installed a portapotty on my O'Day 25 (for sale at a great price by the way) and I have it in the back of my mind. I feel like the pump works well as it has no issue pumping out a full bowl of water. I hoped I would not have to but it looks like I'll have to trace the pluming and see what I can see. I guess it never hurts to go searching through the depths of your boat, never know what your going to learn.
 

Apex

.
Jun 19, 2013
1,197
C&C 30 Elk Rapids
wet mode versus dry mode is pump related. I just changed out to new Raritan pump as the previous would not pull water from lake in wet mode, but worked just fine in dry only mode.
 
Dec 2, 1997
8,708
- - LIttle Rock
I guess it never hurts to go searching through the depths of your boat, never know what your going to learn.
Amen!

And I just realized that you said in your first post that your boat is a C-30, but I'd forgotten that when I based my MSD portapotty recommendation on the 25' Oday in your info box that's at the left of all our posts. It's a great idea for a boat that size, but not necessarily the best idea for a C-30.
--Peggie
 
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