[masterofnone]

Hi all. So Ive been staying in a slip at Lands End Marina in Apollo beach. This weekend I pull up to the pumpout dock and was told "were not going to pumpout this boat anymore, it breaks our pumpout" . I thought he was kidding, but no. So I talk to the service manager, Kevin, and he says he doesnt know why but everytime I come in to pumpout the pump fails. Well Ive pumped out twice, The first time it failed at the end of the tank, the second time it pumped me out fine and rinsed fine and clunked out at the next boat. I kinda hinted at Kevin ya think it might be a coincidence? He says nope , must be my boat.

First, anyone ever heard of such a thing? a msd design that can break a muck pump?

My msd has been in constant use since I installed it 7 ago. At once a week its been filled and emptied at least 300 times. Standard raritan ph2, 15 gallon polyethylene tank. 1 1/2" pumpout hose with a macerator Td off of that line. No y valve. 1/2" vent line. Anything in the tank had to pass thru flapper and joker valves. There was no mention of finding anything that wasnt supposed to be in the system found when servicing the pumpout pump.

the pumpout pump is the piston design with 2 muck valves. One of the muck valves failed twice, which was the failure point.

I offered to have the service manager inspect my system, he declined saying he wouldnt know what he was looking at.

I mentioned it was low tide both times I pumped out, he said "why would that make a difference?" lol

 

[RichH]

Check your holding tank vent line for blockage ...... crud that has 'solidified' in the vent line, mud-dauber nest(S) built inside the vent line, kinked/collapsed hose, delaminated hose, etc. etc.
If the tank's vent is not open and 'free flowing', and your 'head valves' are tight and strong ... a pump-out will stall when the tank develops high vacuum from the pump-out pump .... can break the pump-out's diaphragm, over the load the pump motor, break valves (.... all expensive repairs).

Best probable way to check is to get a 12vdc small volume air pump, and with the 'deck fill' open, pressurize the tank through the vent. If you dont have air coming back out the deck fill when pressurized, the vent line is probably blocked.

Also/BTW, if you have a 3-way overboard valve, be SURE that valve is full open for flow BETWEEN the holding tank and 'deck fill'.

 

[masterofnone]

Check your holding tank vent line for blockage ...... crud that has 'solidified' in the vent line, mud-dauber nest(S) built inside the vent line, kinked/collapsed hose, delaminated hose, etc. etc.
If the tank's vent is not open and 'free flowing', and your 'head valves' are tight and strong ... a pump-out will stall when the tank develops high vacuum .... can break the pump-out's diaphragm, over the load the pump motor, break valves (.... all expensive repairs).
/QUOTE]

You sure about that? Im thinking of the time while the pumpout runs with the valve closed, which it does to varying lengths every time its used. The vacuum always seems to stay a steady and doesnt build to huge levels while the valve is closed. Anyway if the vent line is plugged it simply draws air through the head. Heard it do that over the years when the vent had become clogged, Its easy to tell when the vent hose is plugged. The odor coming from the head as the day warms tells the story quickly.

The hose is old vinyl msd hose. Hard as a rock, intended for the application.

Did a google of msd causing pumpout failure and got no relevant hits. Thought Id throw it up here, also will find pump model and call the manufacterer.

 

[miatapaul]

Have you taken a look at your diet?

 

[Don L]

well that is bull ****

time to go higher up than Kevin

 

[TomMaine]

They're crazy! Pump out pumps in our area have ball valves,the end. It does,not damage them to run them with the ball valves,closed.

 

[capecodda]

Agree, their bad, not yours.

Pretty cold...when your _____ is not welcome here.

 

[krisscross]

The pump could be breaking from hard solids or some chemicals. I'm sure they have pumped out boats at all levels of tide, so low tide is not likely a factor.

 

[sprega]

well that is bull ****

time to go higher up than Kevin

Ditto that, time to go above Mr. Kevin.

 

[RichH]

Check your holding tank vent line for blockage ...... crud that has 'solidified' in the vent line, mud-dauber nest(S) built inside the vent line, kinked/collapsed hose, delaminated hose, etc. etc.
If the tank's vent is not open and 'free flowing', and your 'head valves' are tight and strong ... a pump-out will stall when the tank develops high vacuum .... can break the pump-out's diaphragm, over the load the pump motor, break valves (.... all expensive repairs).
/QUOTE]

You sure about that? Im thinking of the time while the pumpout runs with the valve closed, which it does to varying lengths every time its used. The vacuum always seems to stay a steady and doesnt build to huge levels while the valve is closed. Anyway if the vent line is plugged it simply draws air through the head. Heard it do that over the years when the vent had become clogged, Its easy to tell when the vent hose is plugged. The odor coming from the head as the day warms tells the story quickly.

The hose is old vinyl msd hose. Hard as a rock, intended for the application.

Did a google of msd causing pumpout failure and got no relevant hits. Thought Id throw it up here, also will find pump model and call the manufacterer.

Probable/possible scenario .... and with a vent blockage on your tank, and with your 'overboard' and Y valves closed: The pump-out pump is probably a 'positive displacement' pump (diaphragm-type or piston type) and unless there is a relief valve ('vacuum relief' in this application) its easy to stall, etc. such a pump and 'break something'. That the marina didnt have such, or wasnt operative, is really their responsibility. If this is the cause, then its damn lucky that the marina didnt 'implode' your holding tank.

 

[SVAuspicious]

Going over Kevin's head may be as simple as calling FDEP and telling them a certified (registered? whatever) pump-out facility refused service. The state government probably won't be entertained.

 

[capttb]

I don't see how that is possible.
It's a vacuum pump that draws a vacuum on a tank, the hose is connected to the tank not the pump, so the pump never pumps anything but air. You can pump gravel with such a system, in fact larger truck mounted units are used to clear storm drains of dirt and rocks. And some of us still require an occasional visit from the "honey" truck to pump the 800 gallon MSD buried in our backyard.

 

[hellosailor]

"may be as simple as calling FDEP and "
Great minds think alike.(G)

If they received public funding, they'd be obligated to take all comers or else give the money back, I'd guess. I'd just make Real Damn Sure my head wasn't the problem and was in working ordure. So to speak.

Of course calling in the FDEP is likely to cause some kind of retaliation from the marina, down the line. Might be better to see the owner and diplomatically suggest you don't want to call the FDEP but the bozos aren't giving you any choice.

 

[RichH]

I don't see how that is possible.
It's a vacuum pump that draws a vacuum on a tank, the hose is connected to the tank not the pump, so the pump never pumps anything but air. You can pump gravel with such a system, in fact larger truck mounted units are used to clear storm drains of dirt and rocks. And some of us still require an occasional visit from the "honey" truck to pump the 800 gallon MSD buried in our backyard.

If you hydraulically or mechanically overload the power output of the motor and/or its crank system and its piston or diaphragm surface area (pounds per square inch) ... the pump will either stall and break something or break something and stall. Positive displacement pumps need 'relief valves or rupture discs' that open before damage.

 

[rugosa]

Wait a minute! Isn't it their equipment that is back filling your tank and requiring more pump outs than expected, putting excess strain on your equipment, raising your operating costs and causing you more frequent trips to the pump, ramping up the stress on your relationship with your crew and guests, reducing your productivity at work and ultimately questioning why you put up with all this crap

 

[capttb]

Yeah Rich, but none of that is caused by the OP or his plastic tank based MSD system is it ? Other than the pump, which should draw a vacuum on the tank without self destructing, it's a system with "no moving parts" on the users end. How could the design or contents of the OP's MSD overstress a vacuum pump whose limit is always gonna be around around 14.5 psi ?

 

[RichH]

Make the guesstimate assumptions:
A single stage diaphragm or piston pump can easily develop 8" hg. vacuum = -4psig
Typical diameter of a sludge pump diaphragm ~12" Ø = ~120 sq. inches.

(4 lb./in. sq.) X (120 in. sq.) ≈ 500 lb. pump load (ignoring mechanical advantage of the crankshaft) at a dead-headed 8" vacuum.
... sewage diaphragm pump bodies are usually 'plastic' ('filled' polypropylene).

 

[Minnewaska]

So, you're not official full of $hit now?

Sorry, couldn't resist. On the long shot that this isn't coincidence, the advice to confirm an open vent is good. They can often get solids in them from sloshing and heeling. If you confirm that is fully clear, you need to go up the chain of command.

 

[Stu Jackson]

Is there possibly anything else that could have affected your relationship with the marina staff?

 

[wfish11]

If its the muck valve jamming it's not a vent or anything on your boat. it is solid matter that the valve can't handle and it sounds like it is hard enough to damage the valve. Something is in the bottom of your tank, maybe teeth from the macerator, something hard growing down there, toilet parts, someone put something down the toilet they shouldn't have - soft enough for the macerator to grind up into small pieces but hard enough to jam the muck valve. Breaking on the second boat after yours was just that the junk was still in the pump or lines after your boat. You've got a dirty job on your hands.