I have an new old boat. When I pump the head dry the diaphram at the holding tank pumpout balloons out under pressure. I have successfully pumped out the tank at a punp out station and this happens with the y-valve set to either position. Opening the seacock used to pump the tank overboard, releaves the pressure. Any ideas?
Pumping Head Dry builds pressure @ pumpout diaphra
- Thread starter theArchitect
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When you pumped out, did your bowl also empty?
When you went to the pump out, if the vent line was clogged, air had to come from somewhere otherwise the holding tank would implode - opposite of what you say happens when you pump the head dry. So, if you had a clogged vent when you went to a pump out station, your toilet must have emptied also. My guess is that it is the vent line also.
When you went to the pump out, if the vent line was clogged, air had to come from somewhere otherwise the holding tank would implode - opposite of what you say happens when you pump the head dry. So, if you had a clogged vent when you went to a pump out station, your toilet must have emptied also. My guess is that it is the vent line also.
The Bowl Emptied
When I pumped out the bowl emptied. I have not checked the vent line. I thought that the successful pumpout meant the vent line was functioning. Do vent lines have manual valves on them? I'll take a look in the v-berth tomorrow and see if I can locate the vent line and determine if it is operating. Thanks for the feedback!
When I pumped out the bowl emptied. I have not checked the vent line. I thought that the successful pumpout meant the vent line was functioning. Do vent lines have manual valves on them? I'll take a look in the v-berth tomorrow and see if I can locate the vent line and determine if it is operating. Thanks for the feedback!
The way I clear my vent line is with
a simple device I made. I purchased a plunger from Home Depot. I removed the handle and cut a hole from the handle holder to the inside of the plunger. I then put a hose connector in the handle hole and secured it with a clamp. I connect a hose and turn it on with low pressure. I then put it over the vent and pump water into the tank through the vent. Works great for keeping them clear.
a simple device I made. I purchased a plunger from Home Depot. I removed the handle and cut a hole from the handle holder to the inside of the plunger. I then put a hose connector in the handle hole and secured it with a clamp. I connect a hose and turn it on with low pressure. I then put it over the vent and pump water into the tank through the vent. Works great for keeping them clear.
By diaphragm at the tank are you referring to
A manual diaphragm pump in the tank discharge line? If so, it has nothing to do with pumpout, that pump is used to dump the tank at sea. I think Dick and Guy nailed your problem: your tank vent is blocked, which has pressurized the tank--pressurized it enough to put the tank at risk of bursting if it causing the diaphragm in a manual pump to balloon! So do NOT use your toilet again till you've cleared the vent!! Doing so can damage the system and also have consequences you will not enjoy! It's important to make sure the vent line stays open...so backflush it every time you wash the boat and/or pumpout. Tank vents have two functions: 1. to provide an escape for air inside the tank displaced by incoming flushes. If that air can't get out the vent, the tank becomes pressurized, which can result in anything from an eruption in the toilet to a geyser when the pumpout fitting is opened to a burst tank. 2. to provide a source of air to replace tank contents as they're pumped out. If no air comes in, the pump will pull a vacuum, preventing any contents from being pumped out. In your case, the pumpout suction was strong enough to pull air into the tank through the toilet...which is why your toilet bowl emptied. That it was able to pull enough air through the toilet to allow the tank to be emptied (if, in fact, it actually was) says that's one VERY strong pumpout! Strong enough that, if it hadn't been able to get air through the toilet, it most likely would have imploded your tank. So relying on the toilet as an alternative to keeping the vent open is NOT a good idea! No...vents do not have valves...a tank vent should be an unobstructed line from the top of the tank to a thru-hull near the toe rail. It's the smallest hose, so you should have no trouble locating it. The most common locations for vent blockage are the vent thru-hull and the connection to the tank--both the tank fitting and that end of the vent line. Waste spills into the line when you're heeled, dries and builds up in the fitting and hose, and in the thru-hull...dirt daubers LOVE to build nests in vent thru-hulls, making blocked vents VERY common in the spring. I wouldn't recommend removing the vent line from the tank until you've relieved the pressure in the tank by opening the deck pumpout fitting. And I'd do that VERY carefully, with hose at the ready...'cuz unless the pressure in the tank has managed to escape through the toilet, there'll be a geyser out the pumpout fitting. I suggest you also check out the link below...it'll take you to a comprehensive "marine toilets and tanks 101 for dummies" manual that will explain how the equipment works and how to maintain it to prevent problems instead of dealing with 'em.
A manual diaphragm pump in the tank discharge line? If so, it has nothing to do with pumpout, that pump is used to dump the tank at sea. I think Dick and Guy nailed your problem: your tank vent is blocked, which has pressurized the tank--pressurized it enough to put the tank at risk of bursting if it causing the diaphragm in a manual pump to balloon! So do NOT use your toilet again till you've cleared the vent!! Doing so can damage the system and also have consequences you will not enjoy! It's important to make sure the vent line stays open...so backflush it every time you wash the boat and/or pumpout. Tank vents have two functions: 1. to provide an escape for air inside the tank displaced by incoming flushes. If that air can't get out the vent, the tank becomes pressurized, which can result in anything from an eruption in the toilet to a geyser when the pumpout fitting is opened to a burst tank. 2. to provide a source of air to replace tank contents as they're pumped out. If no air comes in, the pump will pull a vacuum, preventing any contents from being pumped out. In your case, the pumpout suction was strong enough to pull air into the tank through the toilet...which is why your toilet bowl emptied. That it was able to pull enough air through the toilet to allow the tank to be emptied (if, in fact, it actually was) says that's one VERY strong pumpout! Strong enough that, if it hadn't been able to get air through the toilet, it most likely would have imploded your tank. So relying on the toilet as an alternative to keeping the vent open is NOT a good idea! No...vents do not have valves...a tank vent should be an unobstructed line from the top of the tank to a thru-hull near the toe rail. It's the smallest hose, so you should have no trouble locating it. The most common locations for vent blockage are the vent thru-hull and the connection to the tank--both the tank fitting and that end of the vent line. Waste spills into the line when you're heeled, dries and builds up in the fitting and hose, and in the thru-hull...dirt daubers LOVE to build nests in vent thru-hulls, making blocked vents VERY common in the spring. I wouldn't recommend removing the vent line from the tank until you've relieved the pressure in the tank by opening the deck pumpout fitting. And I'd do that VERY carefully, with hose at the ready...'cuz unless the pressure in the tank has managed to escape through the toilet, there'll be a geyser out the pumpout fitting. I suggest you also check out the link below...it'll take you to a comprehensive "marine toilets and tanks 101 for dummies" manual that will explain how the equipment works and how to maintain it to prevent problems instead of dealing with 'em.
Ah Ha!
The vent is clogged at the thru hull. I guess I need to build a plunger back flushing device. Thanks everybody!
The vent is clogged at the thru hull. I guess I need to build a plunger back flushing device. Thanks everybody!
Thanks for the advice!
I scraped the thru hull fitting with a piece of mechanic's wire and the toilet now pumps dry without adding pressure to the system. But... After 20 minutes the bowl fills with about 2 inches of water. The Seacock for the water intake is closed. Now what?
I scraped the thru hull fitting with a piece of mechanic's wire and the toilet now pumps dry without adding pressure to the system. But... After 20 minutes the bowl fills with about 2 inches of water. The Seacock for the water intake is closed. Now what?
Is there a vented loop in the intake?
If so, what you're seeing most likely water in the line to the top of the loop running down into the bowl. The solution: pump the toilet in the dry mode longer. If there is no loop, there should be (it goes between the pump and the bowl, btw, NOT between the thru-hull and the pump), 'cuz without one, the only thing keeping water out the bowl when the intake seacock is open is the wet/dry valve...which can fail or be accidentally left in the wet mode. If that happens when you're aboard, someone will notice that their feet are wet in time to close the seacock before the boat sinks...but if you forget to close the seacock when you leave the boat, you're likely to find it sitting on the bottom of your slip. The other possible source for the water is the discharge line. If there's an uphill run from the toilet--either to a loop or all the way to the tank--water left in it will run back into the bowl. How fast it gets back into the bowl depends on the condition of the joker valve...the more worn it becomes, the more open the slit in it becomes...but even a new joker valve won't totally blocked slow seepage...it's not supposed to. Since it takes about 20 minutes for the water to get back into your bowl, if it IS backflow, your joker valve is still in decent condition. The solution: pump long enough in the dry mode to move the water left in the line over the top of the loop. However, whether source of the the water is the intake or the discharge, you'll still always have about an inch left in the bowl. Any more than that is cause to find the reason and fix it.
If so, what you're seeing most likely water in the line to the top of the loop running down into the bowl. The solution: pump the toilet in the dry mode longer. If there is no loop, there should be (it goes between the pump and the bowl, btw, NOT between the thru-hull and the pump), 'cuz without one, the only thing keeping water out the bowl when the intake seacock is open is the wet/dry valve...which can fail or be accidentally left in the wet mode. If that happens when you're aboard, someone will notice that their feet are wet in time to close the seacock before the boat sinks...but if you forget to close the seacock when you leave the boat, you're likely to find it sitting on the bottom of your slip. The other possible source for the water is the discharge line. If there's an uphill run from the toilet--either to a loop or all the way to the tank--water left in it will run back into the bowl. How fast it gets back into the bowl depends on the condition of the joker valve...the more worn it becomes, the more open the slit in it becomes...but even a new joker valve won't totally blocked slow seepage...it's not supposed to. Since it takes about 20 minutes for the water to get back into your bowl, if it IS backflow, your joker valve is still in decent condition. The solution: pump long enough in the dry mode to move the water left in the line over the top of the loop. However, whether source of the the water is the intake or the discharge, you'll still always have about an inch left in the bowl. Any more than that is cause to find the reason and fix it.
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