Holding tank questions

[melp64]

I have compared what I have and the manual and the articles on the holding tank. I think that was written by Jon W. As I am working my way thru the boat I am trying to clean everything. I have not ventured to close to  the holding tank for reasons you can imagine. But today I decided to take a look and see what kinda of crap I will be getting into (the pun was intended). When I first opened I noticed that on the top of the tank Pic 2 there is a small opening with no plug is this supposed to be like that
The first picture is the end of the tank there is a 1.5 hose from the deck to the bottom of the tank, 1.5 line to the top of the tank coming from the head, and a 1 line coming from the stanchion which is disconnected pic 3. shouldn't that line be connected to something?
In the article is shows a macerator pump on the end of the tank mine doesn't have any pump is that dependent on the type of toilet you have?

[Noah]

Do you have an owner's manual? If not, there is one on this website. I believe, a macerator pump was factory standard on all C34s, regardless of what toilet was used. Things may have been changed on your boat over the years. The top of the tank should have the vent hose to the stanchion.

[KWKloeber]

@Dan

I believe the tank should have  90 ell on top for the vent hose. At least that's what my 30 has so it fits under the cubby cover.

Being on the Great Lakes the PO probably removed the macerator, or maybe when she was first commissioned.  Either way, its nothing to concern yourself with (unless you plan on ocean cruising.)

[Jon W]

Hi Dan. The 1.5" hose from the deck to the bottom side of the holding tank is for pumping out (emptying) the holding tank at a pump out station. It should be connected to a cap on the deck that says "Waste".

The 1.5" hose from the head connects the toilet to the top side of the holding tank. When you flush the toilet it empties into the holding tank.

The 1" hose from the stanchion is the holding tank vent, and should connect to an elbow screwed into the top center of the tank as Ken mentioned.

The purpose of the macerator pump is to be able to empty the holding tank overboard thru an anti siphon loop then  out of the seacock. You can only discharge your holding tank overboard where it is allowed. If you're not allowed to discharge overboard where you sail, you don't need a macerator. Check your local laws/rules.

Glad you mentioned the write up in the Tech Wiki. I went back to jog my memory and noticed the last photo is for a different write up. It's correct now.

[melp64]

after reading all the comments I figured all I would have to do is to by a 90 degree elbow and then just screw the hose back on. Well it seems nothing on my boat can be simple. I understand why the vent hose was disconnected and that's because it won't fit with the lid on it. I put a straight edge crossed the opening and there is only 1 inch between the lid and the top of the threaded flange. Does anyone have a picture of the top of their tank??? Does anyone have suggestions on how to vent this tank out with only a 1" gap.

[KWKloeber]

Dan

Is the tank bulged or does your straightedge show it's flat?

What you want is not a pipe ell, but a nylon npt x hose barb elbow.  Then all you have height-wise above the tank is the slightly expanded hose OD plus the thickness of a hose clamp. Or, unnecessary but you use a brass npt x hose barb elbow.

If the hex nut will prevent the hose OD from bottoming out against the tank, get a barb w/o the hex.

[Ron Hill]

Dan : The holding tank should have a hose coming out of the top (1/2") that is attached to the bottom of the port side vented stanchion!!  The only other port is the exit port on the bottom (right) side of the tank.  It goes to the macerator and then to an exit thru hull.
That's all the factory plumbing that there is!!

A few thoughts

[Jon W]

To give a little more clearance between the cover and the hose/elbow I carved a recess in the cover above the elbow.

[scgunner]

Dan,

In pic #1 the shutoff valve for the macerator pump is still in place but blocked off so your boat may have started life with a macerator but who knows what the PO did.