Clogged grinder pump
Short answer
Stop putting anything but waste and toilet paper down the drains, stop using water, silence the alarm if it sounds, and request service. Do not open the basin to clear it. Grinders jam on wipes (even flushable ones), grease, rags, floss, hair and hard objects; the manufacturers' do-not-flush lists are the prevention.
A grinder pump clogs when something the cutter cannot shred, or something that binds as it shreds, gets into the basin: wipes, rags, grease, dental floss, hair, plastic. The pump announces it as an alarm, an overload that trips, a new grinding noise, or a motor that runs while the level stays high. Keen lists solids lodged in the inlet among the reasons a pump will not run at all.
What clogs grinders, how a clog shows at the panel, why some pumps keep clogging, and why clearing one is not a homeowner job.
Safe steps, in order
Nothing here opens the panel or the basin. If a step does not clear it, stop and make the call.
Step 1: Stop the inflow
No more flushing of anything but waste and paper, and as little water as possible. A jammed cutter has stopped the basin emptying; the storage is all you have.
Step 2: Silence the alarm, leave the breaker
Press the external silence control if the horn is going. Do not keep resetting breakers: Myers treats a second overload trip after one reset as a damaged pump, and a jammed cutter is the usual reason it trips.
Step 3: Think about what went in
A new puppy pad, a holiday with extra guests, a flushable-wipes habit, a cooking fat habit, a renovation. The technician will find the object; knowing the source stops the next one.
Step 4: Call the utility if it asks, then request service
Ask the utility who handles a possible clog. The Keen high-level flash on BCSS needs a prompt call, and Gulf Shores Utilities wants to know whenever the red alarm comes on.
What clogs a grinder pump
Straight from the manufacturers' and utilities' lists.
- Wipes of any kind, even if the label reads flushable (E-One). Wipes do not shred; they wind into rope around the cutter.
- Fats, oils and grease (E-One, Keen, Barnes, BCSS). Grease coats the cutter, the floats and the level sensors. E-One adds that garbage disposals do not keep grease and oil out of the plumbing; Zoeller says not to drain kitchen grease down the sink.
- Rags, cloths, towels, socks and underwear (E-One, Keen, BCSS).
- Dental floss and mop strings (BCSS Keen user guide), hair (E-One). Floss is the quiet one: it wraps the shaft a strand at a time.
- Diapers, tampons, applicators and sanitary napkins (E-One, Keen, Barnes).
- Hard and rigid things: glass, metal, plastic, kitty litter, aquarium gravel, seafood shells, cigarette butts, candy wrappers, disposable toilet brushes (E-One).
- Chemicals, solvents, petroleum products, flammables (Keen, BCSS, Barnes), which do not clog but damage seals and stator.
How a clog shows up
A hard jam stops the motor: the overload trips, the level rises, the alarm comes on. Myers describes this exactly: overload trips and the high-water alarm sounds, push the reset once, and a second trip after a brief run means, per Myers, a damaged pump, possibly a clogged grinder. A partial clog lets the motor run but slowly: longer cycles, a grinding or rattling noise (Keen, Myers), more frequent alarms, higher current. A clogged inlet (Keen, Myers) keeps sewage out of the pump altogether, so the pump cycles on nothing while the basin fills.
Why a grinder pump keeps clogging
Keen explains the mechanism: when the Off level sits too high, or debris gathers at the lower float weight, grease and solids build up. If the pump never pumps the basin down far enough, a layer builds, hardens, and feeds the cutter a little at a time. A worn cutter or ring with lost clearance stops shredding and starts winding. And a household habit, wipes or fat, reloads the basin faster than anyone clears it. The repeat-clog visit checks all three: Off level, cutter condition, and what is in the basin.
What we check and do
Pull the pump and clear the cutter and inlet; inspect the cutter and ring for wear and clearance; check the Off level and float condition; clean grease from the floats or sensors; look at the check valve, which also catches wipes; and, where the basin has a grease layer, pump and clean it. On Keen pumps the impeller and retainer plate with its axial slicers are the only field-replaceable grinder parts; a cutter beyond that goes to an authorized service center or means a new pump. Where a Keen pump on BCSS is beyond repair, BCSS supplies and installs the replacement.
Prevention the utilities recommend
BCSS's grinder FAQ suggests a cup of dish soap down the drain monthly and hosing the basin out yearly as routine care, and its Keen user guide says the level sensors may need cleaning when grease obstructs them. Gulf Shores Utilities asks customers to use liquid soaps, because powdered soap scum on the floats is on its list of failure causes. Our what-not-to-flush guide collects every brand's list in one place.
Still not right? Ask from here
Your name, a way to reach you and what the pump is doing. That is all we need to start. Town and utility are optional.
Sewage backing up or overflowing? Stop using water and call now: (251) 850-8031. On a utility-owned pump, call your utility first.
Questions people ask
How do I unclog a grinder pump?
You do not; a technician pulls the pump, clears the cutter and inlet, and checks why it clogged. E-One tells owners not to attempt repair, and Keen and Zoeller restrict disassembly. What you can do is stop the inflow, silence the alarm and call.
Why does my grinder pump keep clogging?
Keen's answer: grease and solids build up when the Off level is set too high or debris gathers around the lower float. Add a worn cutter and a wipes or grease habit and the basin reloads faster than it clears. The repeat-clog fix is the Off level, the cutter and the habit.
Are flushable wipes really a problem for grinder pumps?
Yes. E-One's do-not-flush list says wipes of any kind, even if the label reads flushable. They do not break down in the cutter; they wrap around it.
Can a clogged grinder pump burn out?
A jammed cutter stalls the motor, which is why the overload trips. Myers says an overload that trips again after one reset means the pump is damaged. Repeated resets into a jam are how a clog becomes a motor.
Sources and facts
- E-One owners guide p.3 do-not-flush list: fat/oils/grease; diapers or baby wipes; tampons, applicators, sanitary napkins; wipes of any kind ('even if the label reads flushable'); rags/cloths/towels/socks/underwear; hair; cotton swabs; kitty litter or aquarium gravel; rubber or latex; cigarette butts; syringes; candy/food wrappers; disposable toilet brushes; glass; metal; plastic; flammable or hazardous materials; strong chemicals; seafood shells; pharmaceuticals. P.5: do not attempt to repair the unit yourself. E/One Owners Guide (LM000403 Rev G), eone.com/… (read 2026-11-04)
- E-One user instructions p.15: kitchen garbage disposals do not keep grease/oil out of the plumbing system. E/One DH071 Installation Instructions incl. User Instructions (NA0061P01 Rev H), eone.com/… (read 2026-11-04)
- Keen O&M p.4: never introduce explosives, flammable material, lubricating oil/grease, chemicals/solvents, gasoline, petroleum products; regulators advise against glass, metal, diapers, clothing/socks/rags, plastic, sanitary napkins or tampons. P.9: solids lodged in inlet; grease and solids accumulate when OFF switch set too high or debris around lower float weight; grinder partially clogged; impeller rubbing ring. P.8, p.10: only field disassembly permitted is impeller and retainer plate (axial slicers). Keen Pump O&M-KPCG (May 2022), keenpump.com/… (read 2026-11-04)
- BCSS Keen user guide p.13: do not flush glass, metal, diapers, socks/rags/cloth, plastic objects, sanitary napkins or tampons, mop strings, cooking oils, dental floss; p.14: level sensors may need cleaning when grease obstructs them. BCSS-distributed Keen KPCGSL21 grinder station manual, www.baldwincountysewer.com/… (read 2026-11-04)
- Barnes OGV manual p.3: do not flush glass, metal, diapers, socks/rags/cloth, plastic objects, sanitary napkins or tampons; never explosives, flammables, lubricating oil/grease, strong chemicals, gasoline. Barnes OGVF/OGVH installation manual (Form 108890 Rev X), d1pkofokfruj4.cloudfront.net/… (read 2026-11-04)
- Zoeller FM2167 p.12: do not drain kitchen grease down the sink. FM2903 p.2: do not attempt to service or disassemble pump. Zoeller FM2167 Owner's Manual, 818 and 820, zoellerpumps.com/…; Zoeller FM2903 Installation and Service Instructions, 803/805/807, zoellerpumps.com/… (read 2026-11-04)
- Myers manual p.8-9: overload trips with high-water alarm; push red reset once; trips again after a short run means pump damaged, may be clogged grinder; partially clogged grinder causes noise and overload; clogged grinder inlet. Pentair Myers WG(X)20 owner's manual 23833A744, www.pentair.com/… (read 2026-11-04)
- BCSS FAQ: 1 cup dish soap monthly, hose out yearly; alarm over 15 minutes, contact BCSS or a plumber. BCSS Grinder Pump FAQs, www.baldwincountysewer.com/… (read 2026-11-04)
- GSU grinder pump page: grease or powdered soap scum on floats among failure causes; use liquid soaps. Gulf Shores Utilities grinder pump page, www.gulfshoresutilities.com/grinder-pump (read 2026-11-04)
- From January 1, 2026 all grinder pumps on the BCSS system must be purchased from BCSS and installed by BCSS. BCSS Grinder Pumps page, www.baldwincountysewer.com/grinder-pumps (read 2026-11-04)