Can you explain the cause of cement deposits?

Status
Not open for further replies.
R

Rich Stidger

I have known that over time the sludge in the bottom of the holding tanks turns from mud to concrete and that there is no easy way to remove it. However, I am ignorant of WHY this sludge turns into a concrete-type deposit. To the best of my knowledge, and according to friends that have septic systems at their homes, there is none of these concrete-type deposits in a home septic system. If that is true, why do we have it in our holding tanks? BTW, this past weekend I had the pleasure of rebuilding my head on the hook after a guest plugged it up. I was probably due for a flap & joker valve replacement anyway, but the plug-event was the final straw. During this pump disassembly, I found about a 1/16th inch of cement deposit in the bottom of the pump housing, and almost an 1/8 inch thickness inside of the 2" waste hose to the holding tank. I thought that the cement deposits only formed in the tank itself, not in the hoses. I assumed that the hoses drained down to the tank. At the end of each weekend, or at each pumpout, I pump the toilet 10-20 times to flush the hoses completely. I try to flush the hoses well at each use, but I admit that sometimes liquid waste is not followed with a large volume of water in order to conserve the volume that is put into the tank. I fear that I am ultimately going to need to replace all of my hoses due to the amount of hardened sludge in them. I am in my 6th season of use of my Hunter 40.5. After the first year, I used KO and Odorlos exclusively. What is the expected lifespan of hoses? I have a stainless holding tank and I am planning to replace it at the end of this season and junk the WEMA sensor as well. I only hope that I can get a plastic tank that is as large (30gal) as my present tank. Do you know how I can find the correct model of plastic tank to use as a replacement? TIA, Peggy. Rich
 
P

Peggie Hall/HeadMistress

Boat plumbing and household plumbing have

nothing in common. The build-up in the hoses sea water calcium carbonate (rarely found in septic tanks). The sludge in holding tanks is a combination of sea water calcium carbonates, urine crystals...prob'ly some chemical residue from the first year of use...and toilet paper and solids that weren't in the tank long enough to break down completely, but only dissolved...and have never been stirred up and flushed out. Unlike household toilets and septic tanks, marine toilets and holding tanks require ongoing maintenance to keep them working. Obviously, the idea of rinsing out your holding tank after pumpouts has never occurred to you. Nor, if you avoid even flushing the toilet enough to rinse the waste out of the hose, does it appear that you've ever even thought of flushing some fresh water down your toilet to rinse the sea water out of the toilet and the hoses. If your head hasn't had any maintenance at all in 6 years, no wonder it finally clogged. I'm amazed it took this long! There's nothing you can put in the tank to dissolve the sludge in it..but the hoses can be salvaged with a 12% solution of muriatic acid and water through them. Just flush down it down the toilet, it won't hurt anything in the pump--in fact will dissolve the build-up in it too. As bad as you've let yours get, it may require two treatments to clear all the build-up out of the system. To prevent build-up in the hoses and toilet pump in the future: when closing up the boat, close the head intake seacock (if you aren't already doing that, you're likely to find your boat sitting on the bottom in your slip one of these days), pump the head as dry as possible...then flush a couple of quarts of clean fresh water down the toilet. Follow that with a cupful--no more--of white vinegar. Do NOT leave vinegar standing in the bowl...soaking in vinegar will destroy the joker valve...pump it all the way through to the holding tank. To prevent sludge in the tank, nominally rinse the tank with clean water--enough to stir up any sediment so it can pumped out--after every pumpout or dump at sea...and THOROUGHLY flush out the tank several times a season. Ronco Plastics is the best source for a new tank...they have more than 400 shapes and sizes, over 100 of which are non-rectangular. Their catalog is on their website at http://www.ronco-plastics.com If it were my boat, I'd replace all the hose when I replace the tank and get it over with...'cuz whether they need it now or not, they will. You might want to check out the link below, too...it'll save you a lot of future "head aches."
 
W

Warren

Pump out problems

I finally got to a pump-out station this past weekend, and pumped out the holding tank after replacing the head, hoses and vent line. I was able to get the initial pump-out going OK, however when I attempted to send water down the deck fitting, it would not go into the tank. I also noticed a "high pitched vibration" when I was pumping out the tank. I am guessing that even though I replaced the vent line, it is still not drawing in air. My thought was that if I continued to pump-out I would collapse my tank. Also, I have a macerator pump in-line, and I do not plan on dumping overboard. Would it be OK to remove it over the winter, and connect my holding tank directly to the pump-out deck fitting. Again, my thought is that the pump was keeping the water from entering the holding tank, preventing me from rinsing it out. I eventually just put a hose into the head, and kept pumping fresh water into the tank.
 
P

Peggie Hall/HeadMistress

Remove the macerator

I don't think the vent is causing your problem...I suspect you put the tee fitting in your pumpout line in the wrong place when you replaced the hoses. It has to be between the tank and the macerator (IMO, it should also be a y-valve, not a tee fitting)--ahead of the macerator. If you put the tee after the macerator, the pumpout has to try to pull waste out of the tank through the macerator, which doesn't work very well...it would also explain why you can't put any water in the tank through the deck fitting--the macerator is in the way. That explains all the symptoms you described--the pumpout isn't pulling a vacuum in your tank, it's trying to pull the innards out of your macerator. You can't legally use the macerator to dump tank in LI Sound anyway--you'd have to be at least 3 miles out to sea on the other side of LI...so instead of correcting the problem by moving the tee in the hose, you might as well just remove the macerator altogether and run a hose straight from the tank to the pumpout fitting. Plug the thru-hull, wire tie the seacock handle--or remove it--and run a short section of hose off the thru-hull that's above the waterline at any angle of heel, also plugged. Or better yet (unless your boat isn't big enough to have the power resources to support one) since LI Sound is not "no discharge," put that thru-hull to good and legal use by installing a Lectra/San.
 
W

Warren

Removal of Macerator

I did not install the macerator, this is how the boat came. I also only replaced the hoses from the new head to the holding tank and a new vent line. I never touched the hose from the tank to the pump. Also, I am on the South Shore not the LI Sound. I do sail three miles off shore on a regular basis. I also know that Catalina installed the original macerator pump because I had requested the original order form for the boat and a macerator pump was delivered when the boat was new (1989). I was going to replace all of the hoses, however I noticed that the hose coming out of the holding tank is marked 1 1/8 not 1 1/2, and Ordor Safe only sells up to 1 1/2 hose. I have not checked the deck fitting, although the hose looks the same. The current macerator pump is in a tough spot to reach, and I have not gotten a good look at it. I know from your book the life span of a macerator pump is not that long, so I doubt it is original to the boat. Your suggestions on how to maintain them are quite involved and the PO did zero maintaince on anything on the boat since he owned it. Still think it macerator is plumbed wrong, or could their be another problem. Thanks for any further advice.
 
P

Peggie Hall/HeadMistress

It's not impossible that the factory put it in the

wrong place...people do the work, and people do amazing things sometimes. I've even seen bilge pumps a full foot above the bottom of the bilge. I suspect your tank discharge hose may be mismarked...'cuz I don't know how anyone could get 1 1/8" hose onto a deck pumpout fitting...they all have 1.5" "throats" 'cuz that's the CG standard for 'em. If it really IS 1 1/8, there'll be an adapter in it. Tank discharge fittings are also 1.5" standard. If you have a short piece of OdorSafe hose left, compare it with your pumpout hose...a 3/8" difference should be easy to see. Maintaining a macerator isn't that involved...rinse it out with clean water when you rinse the tank...replace the impeller annually as preventive maintenance 'cuz they never fail when the tank is empty, only when you need to dump the tank. That's about all you CAN do to one. You really do need to crawl around and see what you have...'cuz I can only go on the symptoms you've described...and from 1,000 miles away the only thing that makes any sense to me is a macerator in the way of the pumpout.
 
Status
Not open for further replies.