Photo of a common sewage ejector pump used in a modern basementSeptic Grinder & Sewage Ejector Pump FAQs
Diagnostic questions & answers for sewage ejector or grinder pumps

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Sewage grinder pumps / sewage ejector pump FAQs - diagnostic questions & answers:

This article provides frequently asked questions & answers about buying, installing, or troubleshooting & repairing sewage & septic pumps & how they are maintained

This article series explains the differences between and gives installation and maintenance advice for Sump Pumps, Sewage Ejector Pumps, Septic Grinder Pumps, Sewage Pumping Stations, & Septic Pump Alarms. We discuss sewage grinder pump types, sizes, voltages, horsepower, installation and maintenance.

An Environment One Corporation grinder pump schematic sketch is shown at the top of this article.

Green links show where you are. © Copyright 2017, All Rights Reserved.

Questions & Answers Help Troubleshoot Sewage Ejector Pumps, Grinder Pumps, Effluent Pumps, Septic Pumps

Sketch of a common sewage grinder pump used in a modern basement

How to buy, install, inspect, & maintain Septic tank pumps, septic grinder pumps, septic effluent pumps

What is a Sewage Ejector? Sewage ejector pumps & What's the difference between an effluent pump, sewage ejector pump, and grinder pump? Recommended pipe diameters for sewage pump installations.

[Click to enlarge any image]

Question: Options for battery backup for a sewage grinder pump

For a grinding pump (zoeller 1/2hp)... What options for a battery backup? Computer UPS maybe?? Something more serious? - Rob 8/30/11


Nice question, Rob. I'd look at the data for the Zoeller pump model (data from your installation manual should be enough as the pump itself would need to be pulled to look at its data tags). I am not sure that a typical home computer UPS will have enough ampacity at 120V to handle the pump operation but it might. If not, take a look at battery-operated backups for basement sump pumps.

Or even a second, auxiliary 12-V pump itself, added into the same pumping station (if there's room for both pump and floats).

A second pump (common installation practice) has its float control set to turn on the pump at a higher level than the main pump, so it will operate automagically if/when the main pump stops working for any reason.

Question: Clunking noise coming from the grinder pump when it shuts off

I have lived through a few sump/grinders in the past 6years. HUGE pet peeve is the giant clunk the check valve makes when the grinder shuts off. I have a new house and the plumbers installed a ejector system and everything and looks good.

The main drain outlet pipe is secured to the concrete foundation wall with foam padding between the pipe an the "U" bracket. near the top (12" from the ceiling joist) is the check valve. We are still getting a very large "Clunk" when the grinder stops that shakes main floor.

Do you have any suggested best practices when installing this setup to reduce noise in the overall ejection process?
thnx - Matt 12/27/11


Matt there should be no clunking when your sewage pump turns on and off. It sounds as if the pump is not secured, or as if a mount has broken or come loose.

Question: Chirping sound coming from sewage ejector pump

I woke up today to a chirping sound coming from my sewage ejector pump.

it seems evenly spaced (about every thirty seconds), not very loud, but annoying.

the pump is only one and a half years old.....the pump is near my bedroom and interfering with my sleep

.please help me figure out what that noise is. - Barbara

Reply: check for a bad battery on a DC battery operated sump system or for a problem with the charger

Barbara, a chirping sewage ejector pump - sound as if either the pump motor was unable to start and run or there was a problem with a float control - perhaps setting off an alarm? I'd track the sound directly to the source. Does your system include an alarm?

Look also for a battery - back-up pump system or battery-operated sump pump system whose charger has come diisconneted from the battery or whose battery won't accept a charge.

Check the water level in the battery and if it's low, use distilled water to fill to the indicator rings in each battery cell.

Question: Sewage pump runs all the time - when should the grinder pump cycle on and off?

Are these pumps supposed to run all the time or just when water is being used? - Charlene 5/1/12


Charlene, most grinder pumps do not run every time the water is being used but rather are turned on and off by a float control inside the receiving tank. If your pump is running constantly the float switch needs repair or replacement.

Question: is it possible to repair a leaky sewage grinder pump holding tank?

I have a crack in the bottom of my grinder pump holding tank which is allowing some dirt and debris into the tank. Other than complete removal and replacement of the tank from my concrete basement floor, do I have any other options to seal or repair this crack/leak? - R.H. 1/14/13


It may be possible to empty the sewage grinder pump tank, clean and dry it, and repair the crack using an epoxy crack repair product or for plastic tanks, using a fiberglass patch - depending on tank material, but

Watch out: leaning over any septic tank or cesspool, even a small grinder pump tank that has contained sewage can result in death by asphyxiation; also if there are sparks or a nearby flame, the result can be a methane gas explosion;

Don't work alone, never enter a tank without special training and protective gear/apparatus, &c. - stay safe .

Question: loud noise traced to old pump in basement. I disconnected it and now have septic problems.

(June 17, 2014) Gregory King said:
I bought a home built around 200 yrs ago. im a plumber an have a problem. i had owned my home a few yrs an in the bacement i heard a loud noise.

when i went down i found an old pump running. i had thought it had been out of use for some time by the looks of it. i disconnected it.Im having problems now with septic in home. is the any way this pump has anything to do with the septic or field ?



Some septic systems use pumps for various applications including the grinder pumps discussed above on this page.
If the pump you found has to do with septic you should see it connected to the building DWV system.

I'd need a more complete description or some photos to offer more - you can send photos to us at our CONTACT link found at page bottom.

Question: Zoeller grinder pump check valve complaint

(June 26, 2014) Jason said:
Hello. Had a Zoeller grinder pump replaced at my house. 2 story house. The pump services the below grade level and it looks like they original builder dropped a far kitchen drain in their as well. The old pump was audible throughout the house and to some extent when the check valve close.

The plumber said the old check valve was horizontal and he changed that to a vertical configuration. it's loud as all get out when the valve closes. Plumber says horizontal check valve is not ideal is more easily blocked open. Is there way to slow the closure of the check valve so there is not so much hydrostatic shock.

Now, it reverberates throughout most of the house. I'm worried that is causing way more stress than before.



Thanks for the question, sorry I don't have a good answer. You may be describing a water hammer problem - usually occurring on water supply piping not drains.

I'd give Zoeller a call to ask their opinion about the cause before just treating the symptom.

If the installer failed to drill or clear out the required weep opening in the discharge pipe below the check valve that could also be a problem.


Keep us posted as what you learn will assist others.

Question: sewage grinder pump odor problems

(Aug 25, 2014) karen said:
We are having a problem with odor with our grinder pump in the basement. Is there something that you can flush down the toilet to help with this.


I think I'd look first for a leak, bad venting, a failed check valve etc. If you have not always had odor complaints it makes sense to find and fix what's wrong rather than to just try to deodorize it - a temp fix.

Question: sewer ejector pump with external vault & check valves - lift station: frequent pump cycling

(Sept 19, 2014) Eric LaShore said:
I am considering installing a external vault with a dual check valve to the sewer line with an ejector pump or a lift station with two ejector/grinder pumps (disconnecting my home from the sewer) and I'm attempting to weigh the pro's and cons. I assume the lift station will be more protection against sewer back up but the dual check valve should provide pretty solid protection as well.

I'm interested in determine the avg power consumption of a grinder/ejection pump to determine the increased power consumption destined for my energy bill when installing a lift station. I'm not quite sure how to address the question when dealing with AC power.

(Sept 30, 2014) Jessie said:

Hi! We have a bi-level home (10 years old) at the bottom of a hill from a neighborhood with a grinder/waste ejector pump that pumps ALL exiting waste/water from our house to the main sewer line up the hill from us. The pump/basin is located outside.

It was replaced this summer when it stopped working (10 year old house curse), and ever since, the new pump (a Zoeller model) has been running super frequently, like every 5-10 minutes, when no water is exiting the house.

We took it off and watched, and it appears that some ground water is coming into the pump from what appears to be small holes along the side of the basin, that look like they're supposed to be there.

The water will flow in from the ground/outside of the tank, trigger the float, and it will kick on, pump it out, and turn off. the water continues to seep in at a near constant stream - even though we haven't had much rain lately (although we are at the bottom of a hill and our yard does stay wet much longer than most, and our backyard where the pump is is pretty shaded).

The guys that put in the replacement pump this summer came and looked at it and seemed dumbfounded, saying "maybe you should get a backhoe and see where the water is coming from." We were dumbfounded. My husband turned the pump off at the breaker and watched it. After the water seeped in to just a bit above the holes, it stopped.

The water level didn't continue to rise. His theory is that the float needs to be adjusted up a few inches, and that the tank SHOULD be letting in some groundwater, that it is normal and should hold water level to the groundwatever level. Does this sound correct?

The owner of the plumbing company (the dad of the kid who recommended a backhoe!!) is coming to check it out tomorrow, and we're hoping he agrees that we just need to adjust the float up a bit. I'm sure it's not good for the new pump to be running almost non-stop - AND we saw a $40 jump in our energy bill this month.

Do you have any thoughts on the matter?


(Oct 14, 2014) gord said:
should you run large amounts of water through the grinder pump when not in use for six months . We pump up hill 150 ft. should we clear the line of slurrey

Question: worried about sewage staying too long in the grinder pump reservoir

(Oct 17, 2014) Kimmie said:
We live in a city and our house has a pump in the basement. After reading this, I realized it must be a sewage ejector pump.

We've tried not to use the basement toilet because I am afraid that solid waste will stay in the tank for a long time before being pumped into the sewage line and that's not very pleasant. Does waste get pumped out right away or it sits there until there's enough to trigger the pump? Thanks.



Most residential sewage grinder pump reservoirs are rather small and will pump the ejector tank after a few uses of plumbing fixtures.

If you are leaving the toilet and grinder pump un-used for weeks or longer I suggest running sink, shower or tub clean water into the pump reservoir until you hear it cycle twice. That should leave relatively clean, low-odor-source water in the grinder pump reservoir.

Question: grinder pump cycles on and off

(Mar 3, 2015) GARCIA said:
the alarm on the grinder pump is going on and off. When I try to reset as per the instructions, nothing happens.

The level of the water/sludge does not appear to be abnormal. What is going on? We live on a bi/level home. We bought the home 1.5 years ago and this was supposed to be an additional system. Can you explain the possibilities? Thank you


I would look for a failed check valve that allows sewage backflow into the pump or a failed pump control switch, relay, or float.

Question: grinder pump makes humming noise

(Apr 4, 2015) Sheldon said:
Our grinder pump makes a humming noise after it got done pumping, so I unplugged it.
It pumped fine and then I could hear a humming noise, I unplugged it and it stopped and plugged it back in to see if maybe it was just stuck or could reset itself, but it still
hums. I don't want to flush try and start the pump in case it doesn't work. Any ideas?


Perhaps the pump shutoff switch is not working and the pump is running dry - which would not be good for it.


(Apr 26, 2015) steven buonomo said:
What is a good price to funish and install a 2hp ejector/grinder pump ?


Steven there is such a wide range of installations that I can't guess at what the labor portion of your job might be. Sewage ejector pumps range from around $300. to $1000. for residential systems.

Question: sewage pump keeps short-cycling on and off

(May 1, 2015) Suzanne said:
Our home sanitary system was installed 45 years ago with a grinder pump to send sewage 450 feet uphill to join our larger sewer line to the septic tank and field.

The 4 inch plastic pipe leading to the larger sewer line was replaced with a 6 inch pipe with two clean out places. Now the grinder pump is turning on and off every fifteen seconds even when no water is being used in the house. Will the grinder pump for a 4 inch pipe be able to handle the job for a 6 inch pipe?


A short-cycling grinder pump needs to be repaired before it burns out. You may have a switch problem, float problem, a failed check valve (likely) or water is left on and running into the system from a fixture somewhere.

22 May 2015 Serge Duval said:
I can see why problems with a sewer pump would be problematic. This gives a good explanation of what a sewage pump is used for. I also really appreciate the actual photos of sewage pumps. I'm going to keep this article in case I ever end up needing to do repairs on mine. Thanks for the information!

Question: intermittent sewage grinder pump stalling

(May 25, 2015) Judy said:
Having constant problems with septic pump grinding system. Pump works for a week and then stops. Plumber opens system and it starts to work again. Does well for a week and freezes up again. On going issue....does this system need to be vented to prevent a possible vapor lock or something like it. I am totally ne stumped as are the plumbers I've used. Everyone does the same thing with the same results...any ideas?


I would look for

Question: outdoor grinder pump blows fuse

(July 26, 2015) Vince said:
My outdoor grinder pump keeps blowing a 3 amp fuse instantly upon replacement. Also, the pump maintenance alarm light is not working either (not the bulb, I checked it by placing it in another fixture). Would this one little fuse keep the pump from working? What would cause both of these issues to occur?



if the fuse is blowing it's doing its job to prevent a house fire. There is perhaps a wiring error, short circuit, wet connections, or a seized pump motor that needs to be found and repaired. I'd ask for help from a licensed electrician.

Check also that there is no blockage of the float switch or binding of the pump impeller from dental floss or qtips or other crud.

Question: did I buy the right type of pump to stop my toilet from backing up?

July 30, 2015) sly said:
got a sewage pump from lows for my basement the toilet keep backing up did I get the right pump



A sewage grinder pump is used to move sewage (toilet waste) up to a higher drain line or sewer line.

If your toilet is backing up perhaps the problem is a blocked drain or a failing septic system.

Question: what makes a grinder pump vulnerable to burn-up?

(June 23, 2015) Correy Smith said:
How would you determine if a certain material would burn up the grinder pump? My little daughter was playing with the toilet and accidentally flush a huge amount of paper and crayons. Now I have to do a huge sewer pump repair and with little experience


A commonsense approach would be to identify any material that can enter and bind the pump mechanism and that the grinder is not designed to handle. For example Zoeller Pumps specifically says that their sewage grinder pumps (Shark series) are designed to handle anything that is normal to flush down a toilet. Basically that's feces and toilet paper.

See WHAT CAN GO INTO TOILETS & DRAINS? for complete details.

Tampons, dental floss, high levels of powdered laundry detergent, kitty litter, string, are examples of stuff that can do damage.

Question: sewer line broke off and grinder pump was damaged by gravel

(July 5, 2015) Peter said:
The underground drain pipe to my new tank and sewage pump grinder was damaged (broken right off by one of the subs).

At the break, a flow of waste water and sand/gravel was feeding into the tank until the point that about 10 feet of the drain pipe (still connected to the tank) was filled solid with sand and gravel. This may have been happening for a couple of weeks without our knowledge until the water backed up. I am concerned about the tank and pump grinder. What should we do?



The gravel-clogged pipe needs to be cleared or removed and replaced or the system will surely not work properly. It might be worth finding a plumber with a camera to scope the line.

Reader follow-up:

Thank you for your quick reply. Wow!
So...We did clear out the gravel-clogged pipe (had to as the house backed up).

Every where I read (including your site), it says to not get sand/gravel/aquarium stones/etc. into the tank or through the grinder. We have had loads of sand and gravel going through the system now. I am more concerned about the sand/gravel in the tank and the life expectancy of the pump. What is you advice here? I truly appreciate your knowledge and advice here.

Moderator reply:

I agree that any abrasives like sand or gravel, if they make it through the pump, are bad for it. If your pump is still working it makes sense to me to use it until it fails.

An inch or two of sand at the bottom of a septic tank should settle there and be harmless, and should be removed at the next septic tank pump-out.

On the other hand if your septic tank were an aerobic unit or if sand entered an effluent pumping chamber, as a pump would be right there with the sand, I'd go ahead and have the tank cleaned out.

Septic pumper trucks have tremendous vacuum and should have no trouble picking up solids and debris from the tank.

Reader follow-up:

One last question (I hope). What should we know when asking someone to look at the pump for damage?
It is only 3 weeks old and we want to make sure it is in new working condition.

Moderator reply:

Great question. Here are some basics:

1. Is this the right king of sewage pump and is it properly installed - right height, location, secured, wired, switched, accessible ?

2. Is there evidence of damage or malfunction in the pump itself or switch or controls etc.
Signs of malfunction besides simply not running when it should might be missing check valve(s), flow back into the tank, clogging, tipping over, or tank flooding.

3. If questions 1 or 2 cite defects, what's the proper repair.

Question: Septic pump not pumping water out

(Aug 23, 2015) Betsy said:
Septic pump not pumping water out pump does work line to drain field not clogged new pump float septic pumped out last month septic alarm keeps coming on, if I open pit where pump is and move the float pump does come on and starts pumping water out. Pump is 10 years old. It's like the pump float isn't telling the pump to come on when it should no one can seem to figure out why the alarm keep coming on .

I know it comes on because the pump isn't coming on to pump out the water and it get too high, pump float line not tangled up w/anything, if I lift the pump float the pump does come on, checked opening on pump not plugged ---very frustrating



If you watch the pump float switch and it moves up when wastewater rises in the sump pit but if the switch doesn't turn on the pump I'd replace it.

More causes for failure of the septic pump to pump wastewater out are in the sewage pump diagnostic table at SEWAGE PUMP DAMAGE & REPAIR

Betsy says:

thanks- I had a new pump float put in,, new pump. .....

Mod Says:

So do we know if the problem was the switch? Replacing the whole pump might follow if the switch replacement didn't work.

Question: condoms got stuck in the pump

(Oct 8, 2015) Brendan said:
Hi, I have a big problem. We had a plumber come fix a few things and in our basement bathroom he said condoms got stuck and he can't cover it through our insurance etc. Is there any affordable way for me to do it myself? Thanks in advance.


Brendon: contact the manufacturer or their service rep for your pump. Some pumps can be repaired in the field but some problem such as disassembly and recondtioning of a grinder assembly must be done by an authorized, trained service rep. See SEWAGE PUMP DAMAGE & REPAIR

Question: noisy aerator pump, worn bearings

(Oct 28, 2015) Mike said:
I have a noisy aerator. My septic company says that the bearings are wearing out, but they recommend deferring repair/replacement until they stop functioning. Is that good advice? I am concerned about stinking up my yard and neighborhood.


What we don't know is how long a screaming pump with bad bearings will continue to shriek before it stops. I'd replace it.

But if you want to squeeze out all the life you can from the pump, If you check regularly that the aerator pump is still working you should be ok

Question: grinder pump flurry doesn't break down and clogs drainfields?

(Nov 18, 2015) Janis said:
I've heard that the "flurry" created from a grinder pump does not break down in the same way as regular sewage and can cause clogs in the septic drainfield. Is this true? Is there a way to prevent this?



I think you're referring to a slurry - of ground sewage + wastewater.

Ground sewage slurry breaks down just the same as regular sewage, though most-likely faster and more easily.

An issue to watch-out for would be sending ground sewage into a conventional septic tank that lacks a proper outlet tee or baffle: pushing ground sewage into the drainfield destroys it rather quickly. For maximum drainfield protection you'd add a septic filter at the outlet tee (also adding more maintenance).

Question: Can laundry detergent in powdered form clog up the sewage pump?

Can laundry detergent in powdered form clog up the sewage pump? In my opinion it does but my installer says naah. We used powdered detergent, and my wife thinks more is better. Now our pump is clogged with some white crud. - John

Reply: maybe

Solid laundry detergents can form soapy blobs that clog drains or pumps;

I'd go back to liquid detergent and perhaps experiment with different brands if you don't like how the detergent smells. And I"d check with the manufacturer of your HE front loader (what's that a high efficiency washing machine?) about odors. I'm not confident that changing from powder to liquid should explain the issue.

Dosage or detergent brand or even a contamination in the system might.

Question: can polyester fiber clog up our septic macerator pump?

(Dec 6, 2015) Shelley said:
my husband works as a installer of insulation in commercial building. My question is can over a period of time this polyester insulation he is covered in everyday cause our masarator to break from being clogged up? A reply asap would be very nice.


I don't know Shelly but it seems unlikely; you're talking about very small individual fibers. I would however recommend a filter on your washing machine drain.

Question: Our Zoelner Grinder Pump got clogged with toilet paper

2016/04/05 Thomas Guastavino said:
We have a Zoelner grinder lift pump that recently clogged with toilet paper when to wrapped around the impeller. Are there any recomendations for what type of TP is best to prevent these types of problems?


A detailed reply to this question is at SEWAGE PUMP DAMAGE & REPAIR

Question: unsafe sewage coming up in shower

(Nov 7, 2015) Marie said:
We have a grinder pomp under our sink in a basement apartment we are renting. There has been an oder since we moved in.

We are wanting to know if we should be concerned for our heald. We recently had a problem with sewage coming out of our shower. The only separation from it is a box built from 1/2" press board. Thank yo

Corrections: pump, health and you


Marie both items you cite are potential health concerns and may be even more immediately unsafe:

sewer gases contain methane that can be explosive if it accumulates indoors

a sewage backup, if not properly cleaned-up, could leave bacterial and other pathogenic hazards in the building.

Notify your landlord face-to-face and also in writing of these unsanitary and potentially unsafe conditions.

Question: drains back up in rainy weather

(Nov 14, 2015) Chuck b said:
I have problems with my drains when there is significant rain. I my house is actually about grade level, ( crawl space below grade). Therefore there is very little drop in the drain to septic tank and the drainfield is also on this same plane.

Would installing a pump in this application appropriate?

I realize that landscaping would also help with surface water absorption but the drain system doesn't have the ability to apply much head pressure to force effluent to drainfield.


Check fie surface water or roof runoff leaks into the septic tank or flooding the drainfield

Question: grinder pump versus effluent pump - what's the difference?

(Apr 14, 2016) Hazel Owens said:
I didn't know that grinder pumps were made specifically to handle sewage water. I'm glad that you made the distinction between sewage grinder and sewage effluent pumps. It's nice to know where my water is going and how it's dealt with after its use. Thanks for the information!

(Mar 15, 2016) Tracy said:
How you tell the difference between a grinder pump and an ejector pump?

Reply: Effluent pump handles clarified effluent not large solids; grinder pump grinds and pumps solid sewage waste, feces, toilet paper.


Indeed pump names can be confusing because manufacturers may offer models that are in a sort of "limbo" land between a true sewage grinder pump and a pump designed to handle effluent or water only. But basically, yes, if a pump is to handle toilet waste, it needs to be a grinder pump.

Too often people install a pump with less ability to handle solids and it clogs up and gives trouble.

Sure Tracy, thanks for asking.

People often mix up or use these terms interchangably and in error, even some plumbers. Speaking correctly,

A sewage grinder pump is able to pump actual sewage, that includes feces and toilet paper by grinding the sewage to a slurry that is then pumped to a destination -either a public sewer or a private septic tank.

An ejector pump is designed to pump only clarified effluent - that is, liquid, NOT solids. Typically an ejector pump is used to pump liquid effluent out of a septic tank pumping chamber up to an effluent disposal system such as a septic drainfield or soakaway bed found in a private septic system.

An ejector pump might also be used at a laundry to pump graywater up to a public sewer or private septic system or private drywell.

For completeness, a "sump pump" is intended to pump only water, such as groundwater seeping under a basement floor slab up to a groundwater disposal system such as a pipe that discharges to an approved storm drain (not allowed in some jurisdictions) or to a drywell, or to an area of surface runoff.

Typically a sump pump is used in a basement or crawl area de-watering system. On occasion we see someone using a sump pump to pump laundry sink graywater.

Question: will baking soda harm the ejector pump?

(Apr 19, 2016) Diane said:
I have an ejector pump in the basement where my parent say. They have a slow drain in the bathroom, can we use draino, baking soda, baking powder?


Used at normal levels those won't hurt the ejector pump; you'll want to thoroughly flush out the system after using such products however.

Question: rotten egg smell from sewage pump

(May 17, 2016) Patrick said:
Rotten egg smell coming from upstairs sink EVERY TIME my sewage ejector pump runs. It is connected to my downstairs bathroom, and no smell coming from downstairs just the kitchen sink. I have flushed the vent on the roof but no joy. any tips?


I'd check the pump's venting piping as I suspect it's clogged, leaky, or absent

Question: Should ground water be allowed to seep into the grinder pump chamber?

(June 29, 2016) Bill said:

Hi, Our township is starting the process of installing a grinder pump system. Once it is in, of course, we will have a monthly sewage bill.

The pump and the tank will be in the ground outside. Are these water tight or will ground water be able to enter the tank and make the pump run, "pumping" up my sewage bill? (I'm not sure yet if our bill will be based on usage or a monthly set fee.) Thanks.


The outside tank should be water tight.

Question: are chemicals required to dissolve sewage in a pump system?

John said:
Are chemicals used in sewage pump systems to dissolve solid waste?


Not normally, John. Certainly not in regular use. The sewage pump uses a grinder to macerate solids that are then pumped along with the wastewater.

Question: Noise and odors from kitchen sink when sewage pump cycles

(Sept 20, 2015) Jerry said:

We have an ejector system, sump pump and septic tank. Our house is a quad level with a half bath on the lower level. When using the lower level toilet, about every 5th flush the kitchen sink makes a noise and there is slight septic smell. We have had a master plumber out, added a Oatey sure-vent, and have checked the venting.

There was a slight crack in the lid of the ejector pump but we caulked it. The problem continues. HELP!!



I'd look for a sewer line blockage first. Sometimes the first few flushes are simply filling the waste pipe up to a point of blockage that is a bit far down the line. The next flush fills the line enough that the slow passage of waste past the partial blockage causes the gurgling you describe. Just guessing.

Also check for leaks in the vent system for the grinder pump.

Question: Sealant for lid on a duplex Liberty grinder sewge pump system

(Oct 3, 2015) A.L. said:

Help please! We have a duplex Liberty grinder sewge pump system and the basin located inside a "finished" basement. The house is less than a year old. We have a lot of vapour and smell which seems to be escaping through the lid which will not sit properly on top of the basin .

It was suggested that the concrete floor is "to high" and is preventing the lid from sitting tight. The plumber has put a new gasket end sealed it with new bolts but it still leaks .

Can you recommend a sealant that can be used to caulk around the outside of the lid that will adhere to both the concrete of the floor and the metal of the lid? Of course it also has to dry or cure under damp conditions.


Something is wrong with this system: a bad lid, bad gasket, damaged pump chamber.

You should not have to use a caulk or sealant on the lid. If you must, clean the surfaces and use a silicone caulk, understanding that every time you inspect or repair the system you'll have to cut away the caulk.

Why not give the product manufacturer a call to ask for advice?

Question: shutting down a grinder pump when house is vacant

(Oct 12, 2015) Becky said:

I will be leaving the house vacant for six months. What should I do to maintain the system? Should I manually fill it, use Rid Ex and unplug?


It might be nice to run enough fresh water through the grinder pump that it cycles a time or two to clean and then (mostly) empty the pumping chamber.

I would not add any chemicals or treatments.

Question: grinder pump runs for no reason

(Nov 23, 2015) Jean Picard said:

Sewage grinder pump that start by itself?

I have a sewage grinder pump that work well all year long in a finished basement for years.
However, in spring, the pump is sometimes working without any tap or toilet 'input'.

How is it possible? Is is possible that water from the outside get access to the grind pump holding tank (a crack by example)?



Before replacing the float switch and assembly that turns the grinder pump on and off, open the cover to the pumping chamber and watch it; you could have ground water leaking into the system or you could have a running toilet or other drain source that you'd not noticed.

A detailed diagnostic procedure for grinder pump running when it should not can be read at SEWAGE PUMP INTERMITTENT CYCLING

Question: environmental or forensic lab test on white blob of material that hangs up my pump float switch?

Jan 31, 2016) Emory Gose said:
Is is possible to send you a small zip lock bag with an off white blob of material that apparently hangs up my float?
If I know what this is maybe we can discontinue its use?



Please do not send us lab samples. Our forensic lab is on special assignment.

Typically white blobs of gummy muck in the sewage pump are detergent but possibly of course something else. You may want to use one of the national test labs such as EMS.

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