Dockside pump out collapsing the tank

H

Hap-E-Cruzer

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I have a 2001 SeaLand vacuflush system with a couple of issues.

The vacuum pump cycles about 80 times before shutting off. This happens on both heads. I do not know when or if these have ever been serviced. Any suggestions?

The other problem (and critical at this time) is after using the dockside pump out I noticed the tank collapsing while I was in the engine room watching the tank during the process. It collapsed so bad that it pulled the outlet fitting out of the plastic threads in the tank causing a hugh vent leak and bad odor every time it's flushed. After I repair the damage how can I prevent this from happening again when I pump out?
Thanks in advance.
 
You holding tank vent is blocked.

This could be a kink in the hose, bugs in the vent line ( they love it ), or a clogged vent line filter ( esp if at any time you have over-filled the H/T ).

It goes without saying that you really need to fix this.

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Clogged vent might be causing the issue with the VAcu-flush, as well. I'm not a VF guy, so I don't know for sure.

But the collapsing tank is definitely a compromised vent. No 'bout a doubt it!
 
Fix the lack of air flow in and out of the tank. If you only have one vacuum generator you should replace the duckbills on both sides. A little more information is needed do both heads work off the same vacuum pump? How about the same waste tank (it sounds like you only have 1 waste tank to me)?
Bill
 
Add an additional vent if possible after you unclog the 1st tank vent.
Then periodic checking for bugs or inspection of the hose to the vent fitting, an in line filter if you have one (once they get wet they are toast).
Bill
 
Obviously your vent is clogged, probably because of a clogged filter

Is nothing has been done to the heads in 10 years it wouldn't be a bad idea to replace the duckbills, 2 on each side of the pumps (inlet and outlet) You ll k
Need 4 per pump
 
quote:
Originally posted by PascalG

Obviously your vent is clogged, probably because of a clogged filter

Is nothing has been done to the heads in 10 years it wouldn't be a bad idea to replace the duckbills, 2 on each side of the pumps (inlet and outlet) You ll k
Need 4 per pump

Click to expand...

+1
 
Sorry, I didn't give enough info.
We have two heads with two vacu-flush systems. There is only one holding tank. I replaced the vent filter a few weeks ago due to a slight odor the admiral noticed. The old one was full of liquid. I have not tried to clear the vent yet, guess I'll crawl around in the engine room a little more until I find it..
Today I repaired the fitting at the output side of the holding tank, also cleaned and flushed the tank several times. All odors are gone when flushing but still cycling too many times at the vacu flush pumps. Is this possibly caused by the vent too? Any good sources for duckbills? I have no experience with these so any help is appreciated.
Thanks guys for the replies....
 
Duckbills are cheap so it really doesn't matter. Boatfix, west, whatever is the most convenient. The sealand duckbills are standard for all VF and discharge pumps
 
If your tank is collapsing when you pump out, it means that no air is getting into it to replace the fluid you are pumping out. The only way that can happen is a clogged vent line. You should get rid of the filter completely and then flush water from your vent into your tank.

Filters are a bad idea, they only mask the odor and clog up. A properly functioning holding tank will have no odor.
 
Thanks guys,
I'll check that vent today. Wish I had known about that vent filter before buying the new one. Oh Well, that's boating...
 
quote:
Originally posted by Hap-E-Cruzer

Thanks guys,
I'll check that vent today. Wish I had known about that vent filter before buying the new one. Oh Well, that's boating...

Click to expand...


That's why you should always check here first!
 
quote:
Originally posted by HOGAN

If your tank is collapsing when you pump out, it means that no air is getting into it to replace the fluid you are pumping out. The only way that can happen is a clogged vent line. You should get rid of the filter completely and then flush water from your vent into your tank.

Filters are a bad idea, they only mask the odor and clog up. A properly functioning holding tank will have no odor.

Click to expand...


I agree.
 
quote:
Originally posted by HOGAN

A properly functioning holding tank will have no odor.

Click to expand...


The problem with that is most tanks do not have large enough and/or enough vents to function properly. As in allowing enough clean fresh air to circulate in and out of the tank to keep aerobic bacteria growing.
 
quote:
Originally posted by rawidman

quote:
Originally posted by HOGAN

If your tank is collapsing when you pump out, it means that no air is getting into it to replace the fluid you are pumping out. The only way that can happen is a clogged vent line. You should get rid of the filter completely and then flush water from your vent into your tank.

Filters are a bad idea, they only mask the odor and clog up. A properly functioning holding tank will have no odor.

Click to expand...


I agree.

Click to expand...


Agree in theory but perhaps not in practicality depending on the setup. Saint Max has a vent filter. As a matter of fact I need to rebuild it ($12.00) via the instructions posted by one of the RO's as opposed to spending $50 to $80 for a new one.

IMO, the problem is the vent filter hose is so small in diameter, it would do nothing for natural waste decomposition. Unfortunately, it goes from the tank to the filter at that diameter. Changing it to a larger diameter would be an undertaking. The vent line on my Regal was larger than a garden hose. Never a problem and no need for a filter there.
 
Sucking on the deck fitting of a holding tank with a blocked filter is like sucking on a straw with your finger over the other end. Nothing comes out. Suck hard enough and the straw will collapse. Take your finger off the end of the straw and air comes through just fine.
 
And if that doesn't fix it you can make your own vent filter much cheaper than buying one.
 
quote:
Originally posted by KiDaIMO, the problem is the vent filter hose is so small in diameter, it would do nothing for natural waste decomposition. Unfortunately, it goes from the tank to the filter at that diameter. Changing it to a larger diameter would be an undertaking. The vent line on my Regal was larger than a garden hose. Never a problem and no need for a filter there.

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Vic (the Headmaster) has written about this many times, Peggy Hall (the Headmistress) also. With large enough vents (1 vent is good, 2 are better) there will be no need for a filter or chemicals. The smell comes down to the type of bacteria that's growing in the tank. With little air flow, and thus little O2, anaerobic bacteria grows and STINKS! But with plenty of fresh air, aerobic bacteria takes over and those little fellas don't stink.
 
I have read Peggy Hall's articles and she recommends CP. I don't believe she is against Enzymes that promote Anerobic bacteria.
Bill
 
Btw with VF if you open one of the ball valves (and keep it open) while pumping out that will allow air to come in the tank If pump out improves and the tank doesn't collapse then you know you have a vent problem

Also i usually don't screw the pump out fitting tight but leave it a little loose so that if the vent gets clogged the vent doesn't become pressurized
 
quote:
Originally posted by Billylll

I have read Peggy Hall's articles and she recommends CP. I don't believe she is against Enzymes that promote Anerobic bacteria.
Bill

Click to expand...


For those that don't know:

CP - Cleans Potties
KO - Kills Odors

Both Raritan products, and both recommended for use with Electro Scan and Purasan Type MSDs. KO is an natural -living- enzyme that promotes aerobic baterial growth (that's the good kind that doesn't smell).
 
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