Pick whichever is closest.
Where is the boat sitting on the lift?
Does it lift normally with no boat on it?
Likeliest cause
The boat is sitting too far back
Before anything electrical, this one is worth ruling out, because it is free.
Too much weight toward the back of the boat makes the lift work inefficiently. The load is not shared the way the lift was set up to share it, and the motor ends up doing more work than the boat’s weight alone would ask for. It shows up as a lift that labors and a lift that strains, and people reach for the wiring long before they look at where the boat is parked.
A four-inch drop on the back I-beam is normal on a sound structure — it is what the lifts we see do under a boat, not a spec. What is worth chasing is a beam sitting lower than it did last season, or lower on one side: that is the structure talking, not the boat. Otherwise what matters is whether it is beyond that, or whether the lift is obviously laboring.
If it is, position the boat more evenly on the bunks next time. How far forward is a question about your particular boat — hull shape, where the engine sits, what is stored in the stern — so it is worth a couple of tries to find where yours wants to sit rather than aiming for a number.
If it is already parked as far forward as it will safely sit and still labors, the question moves from the boat to the lift. On an older setup, wear and cable that has bunched on the drum — among other things — can put the load out left to right as well as front to back, and moving the boat will not straighten that. On an older lift under a newer, bigger boat, where the lift sits in the slip may no longer suit the boat that is on it now. If the cable is bunching, that has a cause of its own and is the place to start. Why cable bunches →
If none of that is it, go back and answer the other way — that points somewhere else. Or send us the details and we will tell you what we think it is.
Likeliest cause
Voltage falling under load
The motor has enough to spin free but not enough to pull the load. On a lift that almost always means voltage dropping on the run out to the dock — a long run, an undersized conductor, a loose connection, or something else pulling on the same circuit.
This is the case where heavier wire genuinely is the fix. How much heavier depends on the distance and the motor, which is what the calculator is for.
Work out the wire size →
Worth checking too: the boat may simply be heavier than the lift is set up for. Dry weight is the brochure number — fuel, water, batteries and the gear that lives aboard all season add up faster than people expect.
BH-USA gives a stop-line of its own. If the voltage at the motor falls below 110 V while it is lifting (or 220 V on a 220 V motor), that is low voltage by their definition and they say to stop using the lift until it is put right. Taking that reading under load is an electrician’s job, and nothing about it requires opening a panel yourself.
If that does not match what you are seeing, or you would rather someone looked at it, send us the details and we will tell you what we think it is.
Likeliest cause
Heat — the motor has run past what it can shed
Heavier wire will not fix this.
This is the fault people spend money on wire for and stay broken. Nothing is necessarily wrong with your run. The motor has been asked for more cycles than it can lose heat between.
These motors are TENV — totally enclosed, non-venting. Sealing a motor against lake air and wasps also seals its heat in, and there is no fan. The nameplate on both the motors we fit reads Time: 15 MIN and Thermally Protected: None.
Read that second one twice. There is no thermal cut-out in these motors. Nothing clicked, nothing tripped to protect it, and nothing will — whatever stopped the lift, it was not a protector doing its job.
The fifteen minutes is measured from cold. It is not fifteen minutes out of every hour: a motor that has already been up and down twice does not have a fresh fifteen in it. It applies in any weather, too — a cool day does not buy extra run time.
What to do now: stop, and give it at least five minutes before you touch it again — longer if it has been cycling hard. The gear plate wants three to four minutes of its own. Then space the lifts out rather than running them back to back.
Pushing past this repeatedly is how a winding is lost, and in our experience heat damage gets treated as misuse rather than a defect.
If it keeps cutting out even with proper cool-down between lifts, something else is going on. Send us the details and we will tell you what we think it is.
Stop
Stop using the lift and let it cool
If there is a burning smell, do not run it again.
That smell can already be the winding, and in our experience heat damage gets treated as misuse rather than a defect. One more cycle to see whether it still works is how a repair becomes a replacement.
Give it at least five minutes before anything else — longer if it has been cycling. The gear plate wants three to four minutes of its own.
Worth understanding, because it explains why nothing warned you: these motors are non-venting and the nameplate reads Thermally Protected: None. There is no cut-out inside to stop the motor when it gets too hot. The Time: 15 MIN rating is a run limit you keep to, not one the motor enforces — and it is measured from cold, in any weather. A cool day does not buy extra run time.
If it has been getting hot on ordinary use, or it smelled hot at all, send us the details before you run it again.
Try this first
Struggling to start under load
A lift that will run once it is going, but labors to get moving from a dead stop while carrying most of the weight, is usually telling you one of two things: electrical, or heat. Starting is the hardest moment a motor has, so a problem that hides the rest of the time shows up there first.
Before chasing either, there is a procedure worth trying, because it costs nothing and it often settles the question:
- Take all the weight off the carriage. Lower the lift until the boat is properly floating and the cables have gone slack.
- Then lift to height in one continuous run. Not in stages, not stopping to check — one lift, straight up.
That avoids asking the motor to break away from a standstill with the full load already hanging on it, which is the moment it is least able to do it.
One condition, and it is the same one as the drum further down. This is a loaded lift you have just told us is straining, so if anything on the stop list at the top of this page is showing — a smell, a strand, a frame that has moved — or if it strains with nothing on it, do not run it at all. The procedure is for a lift that is sound and merely working hard at the start.
If it still struggles after that, the next place to look is electrical. Voltage matters more at the start than at any other point in the lift, so a supply with no margin shows itself exactly here — and the calculator will tell you whether the run is adequate for the motor that is on there now.
Check the wire size →
Worth ruling out alongside it: if the first lift of the day is fine and it only appears after several, that is heat rather than supply, and heavier wire will not touch it. And if the motor hums without turning at all, that is a different answer again.
If the one-continuous-lift method does not change anything, send us the details and we will tell you what we think it is.
Likeliest cause
The carriage is floating
Cable that bunches, crosses over itself or bird-nests on the drum is almost always a slack-cable problem, and slack cable on a boat lift usually means buoyancy.
Two ways it happens, and both end the same:
- The carriage floats when the lift is down. The cable goes slack, the drum keeps turning, and the wraps come back on in the wrong place.
- Wake hits the lowered lift while you are out on the water. Same result, and you are not there to see it happen.
The most useful question: did it always do this? If it never used to and now it does, the answer is usually that the carriage lumber has dried out over the years and floats more than it did when it was new. Nothing broke — the wood simply got lighter.
The fix is to stop it floating: weight the carriage, or add cable weights. The part is a carriage weight and hardware set — a 4 in. I-beam weight with a bottom plate — and it is a straightforward thing to fit.
Worth sorting rather than living with: cable that keeps re-wrapping badly wears in places it was never meant to wear. Send us the details and we will sort the right weight for your lift.
Likeliest cause
The cable has re-wound the wrong way on the drum
If up used to be up and now it is not, this is almost certainly what happened: the lift was run all the way down and past the bottom. The drum kept turning after the cable ran out, and the cable started winding back on the other way round. From then on the controls do the opposite of what they say.
It is a common one, it is usually nobody’s fault in particular, and it is not a wiring problem — so nothing is gained by chasing the switch.
What it needs is to be run back down and re-spooled the right way round. That is not a job to take on with a boat on the lift or a loaded drum, and it is the reason we are not going to talk you through it here: a wound-up drum under load is where people get hurt.
Leave it, and get in touch — it is a quick job for somebody who has done it before.
Likeliest cause
A start capacitor, or something bound in the drive
A motor that hums with nothing on the lift is not short of power for the load — it is not turning at all, or something is stopping it.
Switch the power off, then see whether the drive pipe turns freely by hand. If it is bound, leave it: forcing a jammed drivetrain turns a small repair into a large one, and whatever is jamming it is still going to be there afterwards.
If it turns freely and the motor still only hums, that points at the start capacitor or at the motor itself.
Either way it is a bench call rather than an adjustment. Send us the details and we will tell you what we think it is.
Stop
A circuit fault, not a load problem
Tripping instantly every time, with nothing on the lift, is not the lift being asked for too much. Something is wrong on the circuit itself.
Stop using it, and get a licensed electrician to look. Resetting a breaker once is fine. Anything past that — testing under load, or anything inside a panel — is their work, not a lift adjustment and not a homeowner job.
If you would like us to look at the lift end of it once the circuit is sorted, send us the details.
Likeliest cause
Moisture, or a GFCI doing its job
Tripping only in wet weather points at water getting into a connection — or at the GFCI protecting you from exactly that. Either way it is a circuit fault rather than a lift fault, and it is telling you something true.
Resetting the GFCI is fine. Finding out why it keeps tripping is a licensed electrician’s job, and worth doing rather than living with: a connection letting water in does not improve on its own.
If the lift itself needs attention once that is sorted, send us the details.
Check this first
The belt, before anything else
Switch the power off, then look. The AX-34 belt lives inside the gear plate, and if it has broken or is slipping the motor spins happily while nothing moves. It is the cheapest thing on this list and the most likely.
If the belt is intact, watch what is actually turning — it narrows things down fast:
- The motor pulley spins but the belt does not move. The motor may need an adjustment — the belt is not being gripped.
- The motor shaft spins but its pulley does not. The key has almost certainly come out of the motor’s keyway. Same story if the motor is running and the big pulley on the gear plate has come loose.
If it is the key, it has gone somewhere — usually the boat’s deck, or the water under it — and the pulley or belt may have gone with it. Look from the dock or from the boat, with the power off. Do not climb under a raised boat to find a dropped part; nothing about a lost key is worth being under the load for. People find them sitting on a bow deck more often than you would think.
Beyond that: the cable off the drum or a sheave, or the drive pipe coupling letting go.
Worth knowing before you order anything: a replacement gear plate comes with its belt inside it. You do not need to buy an AX-34 alongside one — the standalone belt is a spare.
Tell us what you found and we can get the right part moving. Send us the details.
Work back from the power
Nothing at all — start at the supply
Simplest first, and stop as soon as something explains it:
- The breaker. Off, or tripped and sitting mid-travel.
- The GFCI — the one in the box on the control cable, or at the outlet it plugs into.
- The switch or the remote. A Gem remote has a battery in it, and a flat battery looks exactly like a dead lift.
- Anything else on that circuit. If the dock lights are out too, the problem is upstream of the lift.
If power is reaching it and the motor is silent, that points at the switch or the motor. Resetting a breaker or a GFCI is fine; going any further into a panel is a licensed electrician’s job.
If it has power and still does nothing, send us the details and we will tell you what we think it is.
Likeliest cause
The belt, slipping or glazed
A squeal or a chirp, worst on start-up, is usually the AX-34 belt slipping — or gone hard and glossy, which does the same thing more quietly.
Switch the power off before you look at it. A glazed belt keeps working after a fashion while costing you lifting power the whole time, so it is worth changing rather than living with.
Same note as ever: a replacement gear plate already includes its belt. The standalone AX-34 is for exactly this — replacing one on a plate you are keeping.
We keep these. Send us the details and we will sort the right one.
Stop running it
Gear plate or a bearing
Grinding or growling is not a noise to run through. It usually means the gear plate or a bearing, and both get more expensive the longer they keep turning.
A worm gear that has run dry is one repair. A worm gear that has run dry for another month is a different one. Grease fittings exist for a reason and are the cheapest maintenance on the whole lift.
For what it is worth going forward: the gear plate and the pipe bearings want greasing a couple of times a season under normal summer use, and more often if the lift works hard. Summer is when it matters — the heat thins the grease and it runs out of where you put it.
Stop using it and send us the details — this is one where waiting costs money.
Likeliest cause
Cable, pulley or a loose bracket
A clunk or a bang usually means the cable jumping a sheave, a worn pulley, or a bracket that has worked loose.
Switch the power off, then look at the cable while you are there. Broken strands mean stop lifting. A cable that has started to unwind does not recover, and the second one is rarely far behind the first — which is why we generally recommend doing both.
Send us the details, or read up on cable replacement first.
Start again →
This narrows down a likely cause from what you can see and hear. It cannot tell you a lift is safe to use, and it is not a substitute for someone looking at it.
