[C320-list] Access to holding tank pump out and vent connections

[Michael Paris]

Hi Scott,
I believe there’s a thread on this somewhere on the C320 site. I did mine a few years back. The easiest way was through the closet in the aft cabin. The back wall removes fairly easily.

Mike P
#734

> On Jun 3, 2019, at 12:58 PM, Doug Treff <doug at treff.us> wrote:
> 
> Scott, 
> 
> I had my medicine cabinet out when I replaced the vent line. I also had it out again when I replaced my head. Keep in mind there may be great differences between our boats. 3 years and over 300 hulls between us. My hoses were easy to disconnect since the vacuum breaker was in the  cabinet. I had ready access to the hose clamps. Not sure how yours is different.
> 
> I'll have to see if I can dig up some of the pictures I took and send them to you offline since the email list doesn't allow attachments.
> 
> --
> Doug Treff
> doug at treff.us
> 
> On Mon, Jun 3, 2019, at 12:47 PM, Scott Thompson wrote:
>> As the creator of this thread I want to comment on some of the answers. 
>> First, thanks to all that replied. Second, I do not think I have a 
>> clogged vent. We had the problem even after a pump out when I was 
>> hearing a rush of air into the vent. At the end of our cruise I pumped 
>> out again and flushed water into the vent while suction was turned on.  
>> A lot of water was sucked in and after the inrush of air was again 
>> audible. Possibly I've had a clog in the past that created a problem. If 
>> I manage to get access I'm going the route that Jeff suggested of 
>> replacing the vent with something more substantial. Third, before 
>> posting I had already done a careful inspection of everything visible 
>> around the holding tank and head. There is no evidence of any leakage or 
>> loose connections. This is why I suspect something amiss with the vent 
>> behind the medicine cabinet. Fourth, someone suggested I pull the 
>> electrical outlet above the settee for access. On my boat it is just 
>> above the cushions, and the opening is way too small for an arm. Plus it 
>> is pretty far from the pumpout fitting on deck or the vent fitting. So 
>> I'm a bit skeptical that I will make much progress there, but will give 
>> it a try if all else fails.
>> 
>> Finally, I originally requested some advice for removing the "medicine 
>> cabinet." I don't think anyone provided tips for doing that. When I 
>> tried to do so, it became clear that I would need to remove the hoses 
>> first, and then it isn't clear how you get them back in there 
>> afterwards. If anyone has thoughts on this process I would welcome them. 
>> I'm thinking that if I get the thing out I might modify it with a 
>> removable bottom to make the process easier in the future. Has anyone 
>> done anything like that.
>> 
>> Scott Thompson
>> 
>> Surprise (#653, 1999)
>> 
>> 
>> On 6/3/2019 9:20 AM, Doug Treff wrote:
>>> I've done the same as Jeff. I'm also in the habit of squirting some fresh water into the vent line before I pump out - In case any debris or insects have taken up residence. The gurgling sound when I pump out after that is evidence that the vent is clear. I still had odor after that job was done. Cured it by switching over to an electric head with fresh water flush. An expensive upgrade but the Admiral is happy.
>>> 
>>> --
>>> Doug Treff
>>> doug at treff.us
>>> 
>>> On Sun, Jun 2, 2019, at 7:25 AM, Charles Holbrook wrote:
>>>>  I put a carbon filter in the vent hose just before the line penetrates
>>>> the hull, behind the medicine cabinet and no more odor.  I got the
>>>> filter at Walmart in their marine supply section.
>>>> Charlie #192Port Clinton, Ohio
>>>>     On Tuesday, May 28, 2019, 1:32:56 PM EDT, Jeff Hare
>>>> <Catalina at thehares.com> wrote:
>>>> 
>>>>  You may have a clog in the vent hose which could have caused the hose
>>>> to come apart at the vent.  That's accessible behind the medicine
>>>> cabinet.  Note that the factory used a larger diameter vent hose, then
>>>> reduced it with a smaller hose inserted in it in order to fit on the
>>>> vent barb.
>>>> 
>>>> We replaced the vent hose and vent fitting on the side of the boat with
>>>> a forespar 3/4" open unit so that the vent would do its job much better
>>>> without needing to reduce the vent line.  Totally cured the smell when
>>>> flushing, but then we only use fresh water flush, so that helps too.
>>>> 
>>>> https://c320.org/mediagallery/album.php?aid=254
>>>> 
>>>> -Jeff Hare
>>>> 
>>