Clogged Head Lines

[USVIMax]

I recently experienced my head discharge hose becoming blocked (with a fitting giving way in a drawer when it was over-pumped!!!), and we finally relieved it with vinegar and brute force.

I am wondering if a short plumber's snake would be a helpful addition, or would that damage lines and thru-hulls??

Max

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[maxi]

It appears that your blockage is at the seacock and not in the head itself, so a sani-snake probably would struggle to get through the choke valve and the anti-syphon loop even before it gets to the blockage.

Patience will work though, as water is a good solvent and will break down your blockage - eventually, during which time you may have to revert to the bucket & chuckit routine. Suggest that when you get the opportunity, you work on the seacock to ensure that you get a 100% opening and that there are no 'lands' to snag the passing materials.



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[HeadMistress]

More important than how to clear a clog is knowing what caused it so you can prevent future clogs.

Unless you're flushing into a tank, the most likely causes are:

1. Someone flushed something they shouldn't have--paper towel, baby wipe, tampon, condom...a one-time occurance that requires manual removal. However, if only waste and quick-dissolve TP have gone into the toilet, it should "melt" on its own if you just wait a bit.

2. Sea water calcium carbonate buildup in the hoses and inside y-valves. I've seen it reduce a 1.5" ID hose to less than 1/2" and while it happens in all systems that flush using sea water, it happens much faster in warm waters. Prevention is much easier than cure: a cupful of undiluted white vinegar flushed through the head discharge hose once a week. White vinegar can also cure it, but it takes longer...close the seacock, flush enough through the toilet fill the hose--but NOT enough to back up into the head unless you also want to replace the joke valve...soaking soft rubber in vinegar causes it to swell and distort. Let it stand overnight. Repeat if necessary.

3. Incomplete toilet flushing. Flushing only as long as it takes to empty the bowl leaves waste sitting in the hose, inside the y-valve etc. The next flush pushes along a little further, but if there's ANY mineral buildup in the hose, it creates a rough surface that traps bits of solid waste and TP...it begins to pile up...and can eventually result in a clog. It's especially important to put enough water down the head to completely rinse out the hose at least once a day...when flushing directly directly overboard the toilet should be flushed long enough to move the waste all the way out the thru-hull and rinse out the hose.

4. Sea life--a barnacle, oyster or mussel--has taken up residence on the thru-hull, partially blocking it. Urine may get through, and even some solid waste...till what doesn't make it past the li'l critter piles up and creates a clog. No way to prevent this one except to take a look under your boat occasionally, especially if you begin to feel any resistance when you flush.

And speaking of resistance...I'm assuming that blowing out a fitting has taught you not to keep pumping the toilet against increasing backpressure. That can also result in a cracked holding tank if the backpressure is caused by a blocked tank vent, or an eruption in the toilet bowl strong enough to bathe the entire head and occupant in waste. Stop flushing immediately when you begin to notice backpressure. If you're sure nothing has gone down the toile that shouldn't have, just wait an hour...then try it again. If it was only an "overload," it will have disssolved enough to pass through. If you still feel resistance, cease pumping and find the cause. However, if you do the proper preventive maintenance--including rebuilding the toilet at least once every 5 years or so--it's unlikely that you'll have any more clogs unless someone flushes something they shouldn't have.


<hr width=100% size=1>Peggie Hall
Specializing in marine sanitation since 1987

 

[USVIMax]

Thanks for such a prompt and comprehensive reply!

I believe what happened was a combination of 2 and 3. I'm pumping overboard, and when we finally cleared the line, there was quite a bit of "scale" in the line. I think we may have overdone the vinegar, as well, since there is some resistance in dry pumping that may be from a swollen joker valve.

Should the swelling go down in time? And, is it OK to use a snake to break the scale out periodically - inserting it after the loop in the outflow hose?

Max

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[HeadMistress]

I'm afraid you'll have to replace the joker valve...it's toast. It should be replaced at least once every two years--annually is even better--anyway. However, the joker valve has nothing to do with whether your head pump is stiff or not...stiff pumping means it needs lubrication.

If you're gonna use a snake to clear the scale out of the lines, remove the hose from the toilet first. However, if you're willing to be a bit patient, several applications of white vinegar (only use white vinegar...it's more acidic than cider) will dissolve it. The toilet's working now...put a cupful through every day (or every day that you're aboard) when it can sit at least overnight and after 4 or 5 times of doing that, it should be clear...then keep it clear with a cupful once a week. If you do that, there won't be any more buildup, so you shouldn't ever need the snake.

It might also be a good idea to remove the loop and the y-valve and soak them overnight in vinegar. If it doesn't accomplish anything else, it'll demonstrate how effective it is in removing scale...but it will "un-crust" places vinegar might not get into just flushing it through.

<hr width=100% size=1>Peggie Hall
Specializing in marine sanitation since 1987

 

[jerryat]

Hi Headmistress!

I agree with your thoughts, but would suggest that while the lines are off, they might as well be 'banged out' against a hard surface as we regularly do while cruising. This is the quickest way I know to remove what appears, in this case, to be a big build-up of calcium carbonate. It's always staggers me just how much there is, and we do it every six months at least!!

A regularly regime using white vinegar will, as you rightly say, help keep things clear.

Good sailing!

Jerry

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