Holding tank vent clogged

JosefR

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Sep 18, 2016
127
Catalina 30 Gulfport, Mississippi
I'm referring to this old thread and hoping the OP or at least someone who has ACTUALLY removed the stanchion can reply.

http://forums.sailboatowners.com/index.php?threads/how-to-clear-the-holding-tank-vent-hose.144796/

I'm not interested in clearing the clog so much as needing to know what I'm dealing with under the deck. This hose passes between the head and the hull with no access other than through a salon cabinet and through the deck. Before I attempt to remove the stanchion, I need to know is it glued down? Will it damage the deck when I pull it loose? Will the hose want to follow it out of the deck? There are two nuts under the bolts, how do they fasten under the deck if you can't put your hands on them?

Any other useful info would be helpful, but my goal here is to either clear the blockage, or at worse, replace the hose.

Thanks.
 
Dec 2, 1997
8,708
- - LIttle Rock
No need to remove the stanchion to clear a vent blockage...that would be using a cannon to kill a mouse! Use a screwdriver blade, ice pick or whatever works to scrape out the holes or slit. You have access to it through a cabinet if you need to remove it. Remove the hose from the TANK and scrape out that end of it and the vent fitting on the tank. Since you seem ready to take the boat apart, now would be a very good time to redirect that energy into installing a new vent thru-hull (use an open "bulkhead" thru-hull fitting, NOT a "vent" thru-hull) and rerouting the vent line out of the stanchion to it.
 

JosefR

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Sep 18, 2016
127
Catalina 30 Gulfport, Mississippi
Well, I have only made a cursory examination of the stanchion, and I haven't found a hole in it. I have observed my water vent overflowing on a water-fill, so I have an idea where it's at, I just haven't seen it myself.

I have just been reading your advice in other threads on a thru Hull fitting, I am very interested in doing this and would save myself any further concern with the stanchions.

Problem there is, I don't know the difference between the kind of fittings you just described. I am going to Google "bulkhead" thru-hull fitting and see if that's something that fits in my brain... and I was just hoping there was some reason that I can drill more holes into my boat, thanks. This does sound like a much better solution.
 

JosefR

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Sep 18, 2016
127
Catalina 30 Gulfport, Mississippi
I just found where you recommended this.
http://forums.sailboatowners.com/index.php?attachments/plastic-thru-hull-fitting-jpg.119417/

I thought I was gonna need a valve on it. So it's ok to just drill a hole in the side of the boat, fasten that fitting, and attach the hose? That's it? That really sounds too simple for anything boat related! This turns my half day job into a 5 minutes job...

Forums are great for getting information to fix things, but in order to find what it is you're looking for you kind of need to know the answer first. Now that I know what your answer is, I'm finding all kinds of posts where you've already told people this.
 
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Dec 2, 1997
8,708
- - LIttle Rock
I see you've just joined us to today...welcome aboard!

If you poke around the right stanchion, you should find a slit on the aft side of it that's a match for the ones for your fuel and water tank vents.

Nope...no valve needed...it needs to be a "two way street" that provides both a source of air and an escape for air. It's a little more than a 5 minute job...but there are other C-30 owners here who've done it who can give you detailed instructions. The thru-hull can be Marelon, stainlesss steel or bronze...but NOT nylon! UV turns nylon into powder.

Now that I know what your answer is, I'm finding all kinds of posts where you've already told people this.
I've been here 19 years...there are many questions about sanitation systems left to ask that I haven't already answered at least once. If you want to have most of the answers on hand any time you need 'em whether you can get online or not, you might consider checking out the link in my signature...
 

JosefR

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Sep 18, 2016
127
Catalina 30 Gulfport, Mississippi
Dec 2, 1997
8,708
- - LIttle Rock
If I were you, before taking aim with a hole saw, I'd get some advice from someone who's knowledgeable about how to go about putting holes in hulls and where to put 'em. Sit tight for a day or two...someone who's done it is guaranteed to chime in here. Meanwhile, you might want to check out the Catalina forums...you'll find a lot of good info about your boat from other owners in 'em.
 
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JosefR

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Sep 18, 2016
127
Catalina 30 Gulfport, Mississippi
Yep. I don't need to do it until Friday, so hopefully somebody will show up and talk about it. I also need to know if it should be glued down?
 
Dec 2, 1997
8,708
- - LIttle Rock
Yep. I don't need to do it until Friday,
Your only priority till you learn how to install the a new vent thru-hull should be to clear the blockage in the stanchion and prob'ly the other end of the vent line too. That'll let you use the toilet without risk of pressurizing the tank and/or let you pump out the tank without risk of either one resulting in cracked tank.

Never use "glue" to seal thru-hull...use a silicone sealant or bedding compound.

Look under the "forums" tab at the top of the page...you'll find Catalina owners....click on it, you'll even find a forum specific to C-30 owners.
 

JosefR

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Sep 18, 2016
127
Catalina 30 Gulfport, Mississippi
The C30 forum is where I started. I thought that's all the website was until you just mentioned it. As far as the block, I'm not staying on the boat, so I'll just be cutting the hose to deal with that problem. When I am on the boat with the raw water valve open is when there is actually a problem because heat will cause the contents of the tank to fill up the bowl. So far everything stays intact with all of the valves turned off.
 

SFS

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Aug 18, 2015
2,065
Currently Boatless Okinawa
Yeah, I saw that post, and I could feel your frustration in your response. Sit tight on that other thread, more people will chime in. Lots of C30 owners on here, and you put it in the right forum. The good news is that you've already had good advice about how high on the topsides to put (or not put) the new vent hole.

Have you solicited help from the Catalina 30 Owner's Association? They have a TON of info and resources on everything related to your boat. Don't know if you have to join to access it though? You can also call Catalina, tell them the year of the boat, and ask them for advice.
 

JosefR

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Sep 18, 2016
127
Catalina 30 Gulfport, Mississippi
I assume that's the good news. Although the 2nd guy sounds like he knows what he's talking about. I'd need to hear Peggie's response to him to know...I got he said, she said going on now...

I kinda thought this group was part of the Catalina 30 Owner's Association. I get confused.
 

SFS

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Aug 18, 2015
2,065
Currently Boatless Okinawa
No, they are actually an organization of boat owners. Don't know if there is a separate entity for each model. (I own a Hunter.) A search of the Catalina subforums (here on this site) may get you that info. Or you could send a private message to Stu Jackson, who owns a catalina 34 and is involved with that association. He could give you the lay of that land. There is another poster here (can't remember who) that is holds some sort of position (technical editor, or similar?) with one of the Catalina associations. Maybe he will chime in.

Don't get discouraged - there are a lot of amazingly helpful people on this site. And in fairness, there are people who will respond to a thread after reading just the title, not the whole thread. Those responses are often less helpful, for a variety of reasons, but they won't know that, as they didn't read the whole thread. It doesn't mean that they aren't trying to help, they just don't have as complete a dataset as you do, relative to your specific issue.

Hang in there, you are on the BEST sailboat forum there is. And it's just that, a forum related to sailboats. No affiliations to a particular brand. They do have a store that sells a lot of cool stuff at competitive prices, including brand specific parts. Check out the store when you need parts, it helps support the site. Very helpful people answer the phone when you call, and they all post here from time to time.
 
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Oct 12, 2012
15
Catalina 36 East Greenwich
This is my first day being active and hope it is ok to add my thought on this stinky subject: we have a 2001 Catalina 36 MKII with the same exact holding tank vent location - in the base of the stanchion adjacent to the port light in the head. It seems as though the designer of this version was trying to reduce/eliminate thru-hulls above the waterline. On prior boats the holding tank and bilge pumps had their associated outlets in more obvious locations...whatever.
On some days it is possible to get a good long whiff of foul air in the cockpit when the head is flushed. My current thought is to relocate the holding tank vent to the aft transom, directly adjacent to the fuel tank vent (and downwind of the cockpit). This would basically mirror the two water tank vents on the starboard side of the transom. Yes, I am asking for opinions on this idea - hope I can handle it!
 

JosefR

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Sep 18, 2016
127
Catalina 30 Gulfport, Mississippi
I suppose while we are asking, why couldn't this tank be vented to one of the two exhaust ports that are mounted on the stern corners? Not sure what those are...but there is dryer vent hose looking stuff running to them.
 
Dec 2, 1997
8,708
- - LIttle Rock
My current thought is to relocate the holding tank vent to the aft transom, directly adjacent to the fuel tank vent (and downwind of the cockpit). This would basically mirror the two water tank vents on the starboard side of the transom. Yes, I am asking for opinions on this idea -
Not a good idea. It does send odor away from your boat, but a long vent line actually increases the odor...your dockmates and anyone on board any boat you raft to will not thank you if you use the head. What you really want to do is eliminate the odor...and that CAN be done by increasing the oxygen to the tank with the shortest, straightest vent possible and using the right tank products. There have been a zillion threads about odor, what causes it and how to prevent it instead adding the odor of a lethal chemical to it, and why vent line filters are a bad idea, especially on sailboats. You'll find 'em if you search for "holding tank odor" or "odor out the vent"...or (stand by for a little shameless self-promotion)... you can save yourself all that searching time by clicking on the link in my signature...it'll take you to the listing for the new edition of my book. Phil has included the entire table of contents in the listing... You'll not only see that there's a whole section devoted to holding tank odor, but a whole lot of other very useful information. I heard from the editor of SAIL magazine that they plan to publish a review in the November issue...watch for it if you're a subscriber. (end shameless self-promotion).

As for why Catalina ran all their tank vent lines into rail stanchions with holes or slit on the AFT side of the stanchion... to keep sea water out of the tanks in rough seas or when the boat is heeled over enough to put the toe rails in the water. It's a fine idea for water and fuel, but a horrible idea for waste because (a) the slit is so small that salt and/or any waste that spills out the tank clogs it up in a heartbeat...and (b) it doesn't allow enough air exchange to keep the tank aerobic.

Josef...those two vents on the aft corners ventilate the engine compartment to get rid of heat and any diesel fumes. Some boats even have blowers...boats with gas engines MUST have blowers as well as passive vents.

Do any of you remember who posted a report with photos about relocating the vent line on his Catalina to a thru-hull about a month ago? I couldn't find it in half and hour searching.
 

JosefR

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Sep 18, 2016
127
Catalina 30 Gulfport, Mississippi
I've been meaning to tell you that I don't see any signature when you post. Maybe that's because I'm on mobile device?
 

JosefR

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Sep 18, 2016
127
Catalina 30 Gulfport, Mississippi
Wow, weird, I just found a comment from myself from 5 years ago to someone in the Amazon reviews of this book. Why was I looking at this book 5 years ago???