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Rowing Machine Repair: Fixes for a Dead Monitor, Skipping Chain, Bumpy Seat & No Resistance

Repair guide

Rowing Machine Repair: Fixes for a Dead Monitor, Skipping Chain, Bumpy Seat & No Resistance

Rower monitor stuck on zero or chain skipping? Owner fixes from Concept2 and Sunny Health documents, and when to call a pro.

Published November 11, 2026

TL;DR: Most rowing machine problems in the manufacturer documents we read are small and cheap to check: a loose sensor or generator cable, a dirty monorail or seat roller, a chain that needs oil, or a shock cord that has stretched. A monitor stuck on zero is usually a cable, a magnet or a sensor, not the whole machine. A chain that keeps skipping is different: Concept2 says to stop rowing and contact it. Air, magnetic and water rowers differ, so follow your own manual.

This guide draws on Concept2 support pages (Model D troubleshooting and maintenance, and PM5 monitor troubleshooting) and a Sunny Health troubleshooting sheet for its SF-RW5515 magnetic rower. We couldn't load WaterRower's pages (they returned 404 errors), so we don't give water-rower advice here.

Quick symptom guide

SymptomMost likely causeFirst checkGo to
Monitor on, numbers stay at zeroCable, model setting, magnet or sensorCable seated, sensor wire intactStuck on zero
Low-battery warning, short battery lifeGenerator or battery faultFresh batteries, generator testBattery problems
Chain skips or runs roughStiff links or worn sprocketClean and oil the chainChain
Seat bumpy, clicking or wobblingDirty or worn seat rollersClean rollers and monorailSeat
Little or no resistanceTechnique, dust, or clutchClean the flywheelResistance
Handle hangs looseStretched shock cordAdjust or replace the cordHandle

Monitor stuck on zero or not counting

Concept2 air rowers. Concept2's PM5 page covers a monitor that powers on and has working menus, but stays at zero while you row:

  1. Make sure the "tach" (generator) cable is plugged in fully.
  2. Check the model type under More Options > Utilities > More Utilities > Product ID. It should read RowErg D/E/Dynamic for Model D, E, Dynamic and RowErgs.
  3. If it still reads zero, unplug the pickup wire that runs from the bottom of the monitor to the flywheel and look for frays or breaks. Replace it if damaged. A cracked port on the monitor means the monitor needs replacing.
  4. If you have a known-working monitor, swap it in. If that one also stays at zero, the pickup wire is faulty. If it counts normally, your original monitor is the problem.

Concept2 also lists hardware faults that mean replacing the monitor: a broken USB jack, buttons that don't work (usually corrosion on the circuit board) and missing lines on the screen.

Sunny Health magnetic rower. Sunny's sheet for the SF-RW5515 says the magnet and sensor must work together, because the monitor only gets data when the magnet passes over the sensor. Its checks, in order:

  • The meter. Cut-off, flickering or faded numbers, or a monitor that resets or stops counting, can mean weak batteries. If new batteries don't help, the meter may need replacing.
  • The seat. If the seat is installed facing the wrong way, the magnets don't pass the sensor and the monitor gets no reading.
  • A test magnet. Wave a separate magnet, such as a fridge magnet, across the sensor. If the monitor counts, the fault is the magnet or the sensor wire.
  • Excess glue. Glue can seep behind the metal sensor piece and block the reading. Sunny says glue on the outside is fine, and you can cut away what is behind it.
  • Wires. Check the wires under the rower and behind the meter for cuts. Sunny suggests taping or zip-tying them out of the way, and says to email support for replacement if any are damaged.

Monitor battery problems

For a low-battery warning on a PM5 when the batteries are fine, or short D-cell life, Concept2 gives a generator test for the Model D, Model E, Dynamic and SkiErg. In short: remove the batteries, make sure the tach cable is seated, and row hard. If the monitor comes on and stays on, part of the generator works. Then install fresh D cells, confirm the model type, and row. If the numbers count, the generator appears to work. If the monitor doesn't come on without batteries, Concept2 says the generator cable needs replacing.

Concept2 notes this procedure won't work on a PM5 with hardware version 500-599 running firmware 20/720, and says to update the firmware first. Its page also recommends keeping firmware current in general.

Chain skipping or rough

On a Concept2 Model D, Concept2 gives two causes for a chain that skips or runs roughly: stiff links, fixed by cleaning and lubricating, or a worn sprocket, fixed by replacing it. Concept2 says that if the chain keeps skipping, the machine should not be rowed and you should contact Concept2 immediately. When replacing a chain or sprocket it recommends replacing both together because they wear together.

Concept2's maintenance page says to oil the chain every 50 hours of use (weekly for institutional users): rub a teaspoon of purified mineral oil, 3-IN-ONE oil or 20W motor oil along the chain with a paper towel, then wipe off the excess. It warns: "Do not clean the chain with any kind of cleaner or solvent, e.g. WD-40."

Bumpy, clicking or wobbling seat

  • Bumpy or clicking. Concept2 says this is usually worn seat rollers or dirt on the rollers or monorail. Clean both, and replace the top seat rollers if it persists.
  • Wobbles side to side. After long use, roller wear loosens the fit. Concept2's fix is to move the bottom rollers to a tighter hole toward the front of the seat, which means removing the seat and using 9/16" wrenches and an Allen wrench. Use its instructions for your model.
  • Seat hits the end of the track. Concept2 says this is more likely for people with long legs and gives a one-inch roller move. If that isn't enough, you'd need an extended monorail from Concept2.

Not enough resistance, or none at all

On an air rower, resistance comes from moving air, so Concept2 says more drive power gives more resistance. For "not enough resistance regardless of damper setting" it suggests technique first: a low stroke rate of 16-20 strokes per minute with hard leg drive, trying damper 10 for a minute or two, then 5, then 1. If that doesn't help, clean the flywheel, since dust can build up inside. Concept2's maintenance schedule lists a flashlight check for dust every 250 hours.

A complete loss of resistance with no noise is different. Concept2 says the clutch isn't engaging because its lubricant is contaminated or dried out, and the fix is a new flywheel assembly, which it sells by phone, not online. That's a call to Concept2 or a technician.

Concept2's documents don't cover magnetic resistance, so check your own manual for how your rower adjusts it.

Handle hangs loose

Concept2 says a handle that doesn't retract fully usually means the shock cord is too loose from stretching or cold temperatures. Warm the cord up first, then adjust the tension, and replace the cord if it's frayed through the outer cover or losing its elasticity.

Black residue and routine maintenance

Black flecks on the monorail are normal, according to Concept2: dirt, sweat, and some material from the plastic rollers. Wipe the rail after use with a cloth or non-abrasive scouring pad and soap and water or glass cleaner. It says not to use mineral acids, bleach or coarse abrasives.

Concept2's 250-hour check also covers stiff chain links, the chain-to-handle connection, shock cord tension, screw tightness, monitor arm joints and flywheel dust. It warns that using a machine with a worn or weakened part such as the chain, sprockets, swivel connector or shock cord may cause injury, and says to replace a part immediately if in doubt, using genuine parts.

When to call a technician

Call the manufacturer or a service company if:

  • The chain keeps skipping after cleaning and oiling
  • Resistance disappears completely
  • The monitor stays at zero after the cable, sensor and swap checks
  • The monitor has a broken port, dead buttons or screen damage
  • A part looks worn through, such as the chain-to-handle connection or the shock cord
  • The rower is under warranty (check your warranty terms before opening it up)

To find someone local, see our guide to treadmill repair near you or browse the equipment repair directory. The repair or replace guide uses the same logic for an older machine, though its figures are for treadmills.

FAQ

Why is my rowing machine monitor stuck on zero?

On a Concept2, check that the generator cable is seated, the model type is right, and the pickup wire isn't frayed. On a Sunny magnetic rower, check the seat orientation, magnet, sensor wire and batteries.

How often should I oil a rowing machine chain?

Concept2 says every 50 hours of use for the Model D, with purified mineral oil, 3-IN-ONE oil or 20W motor oil. It says not to use cleaners or solvents like WD-40. Other brands may differ.

Why is my rower seat bumpy?

Concept2 says it's usually dirty or worn seat rollers or a dirty monorail. Clean them, and replace the top seat rollers if the problem continues.

Is it safe to keep rowing with a skipping chain?

Concept2 says no: if the chain continues to skip after cleaning and lubrication, don't row the machine and contact Concept2.

Sources

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