Maintenance, Corrosion & Winter
Should You Leave a Boat Lift Up or Down When the Boat Is Off?
Quick answer
Up, with the cradle raised high enough that waves pass under it, whenever the boat is off the lift in season. Lift makers give three reasons: a cradle left in the water corrodes and grows slime, swimmers cannot see it, and the cables sit in the water. Down is right in three cases only: a hydraulic lift stored for the off-season, a lift that cannot raise the cradle clear of the waves (then all the way down, never halfway), and while you service the winch.
On this page
Leave it up. When the boat is off the lift for the day or the week, raise the empty cradle until its beams are clear of the water and of the waves that pass under them. That is what the lift manuals say: DECO's owner's manual says "NEVER leave the lower cradle in the water," Davit Master's tells owners to "raise your cradle until it is well out of the water" after launching, and ShoreMaster's hydraulic lift instructions recommend "leaving the lift in the up position to prevent the bunks from becoming 'slimy' and to avoid creating a hidden underwater obstruction."
The other answer, "leave it down," circulates because it is right in three specific situations, and owners have read it in a manual for one of them. The same ShoreMaster document that says up in season says to "store the lift in the down position over the off-season to protect the hydraulic rams." Both are correct; they answer different questions.
- In season, boat off: cradle up, beams above the waves, power off
- Cannot get the beams clear of the waves: lower it completely beneath the water, not partway (FLOE)
- Hydraulic lift, off-season: down, per ShoreMaster and Pier Pleasure instructions
- Empty lift with a canopy: remove the fabric if the boat will be gone for long (FLOE, Sunstream)
Safety: an empty raised cradle is not a platform. ShoreStation's hoist manual says to "never stand or walk on hoist platform while in any raised position," and Davit Master warns that a work platform "is unstable without the weight of the boat on the cradle." Keep children off a raised empty lift, never reach under it, and turn its power off before you walk away. Dock wiring belongs to a licensed electrician on a GFCI protected circuit.
What seven lift makers actually say
No single manual covers every case, which is why the question keeps getting asked. Put side by side, the instructions agree far more than the forum threads suggest:
| Maker and document | Boat off, in season | Off-season or special case | Stated reason |
|---|---|---|---|
| DECO, Ultimate Power Lift owner's manual (2025) | Up, out of the water | None given | "Electrolysis can cause structural damage" |
| Davit Master, vertical cradle lifts owner's manual | Up, "well out of the water" | Not submerged "for prolonged periods" | Submersion "promotes deterioration and electrolysis" |
| ShoreMaster, hydraulic lift box instructions (4,000 to 12,500 lb) | Any position allowed; up recommended | Down over the off-season; removed if the water freezes | Slimy bunks, hidden obstruction; off-season, "to protect the hydraulic rams" |
| FLOE, VSD-3800 and VSD-5000 owner's manual | Up so waves pass under, or completely beneath the water | Remove canopy fabric if the lift is left empty for long | Waves breaking on the cradle beams wear the frame |
| Pier Pleasure, hydraulic boat lift owner's manual | Lock pin in when not in use | Lower completely before disconnecting the pump box | Fluid "may flow slowly back"; hoses are pressurized when raised |
| Sunstream, canopy owner's manual | Not addressed | Canopy fabric off if the boat will be away | Wind "can actually move your boatlift" with no boat on it |
| ShoreStation (Midwest Industries), PWC hoist manual 0004405 | Not addressed | Completely lowered to work on the winch | Safety while the cover is off |
| ShoreMaster, "How to make your boat lift life last" (2023) | Up, out of the water | Not addressed | Cable wear |
None of these makers recommends leaving an empty cradle in the water as a routine. Every "down" entry is an off-season, maintenance or wind instruction.
Why up is the in-season default
Corrosion and growth
Two manuals use the same word for what a submerged cradle suffers: electrolysis. DECO's operating steps after launching end with "Raise the cradle up out of the water. This will prevent deterioration of the cradle from corrosion and electrolysis." Davit Master says submersion "promotes deterioration and electrolysis." A submerged aluminum or galvanized cradle is part of a galvanic circuit with the pilings, dock hardware and nearby boats; a raised one is not. How that circuit eats metal is in boat lift corrosion protection.
Growth needs water too. ShoreMaster's "slimy" bunks are the mild version. On lakes with zebra mussels, the Minnesota DNR lists boat lifts among the surfaces the mussels attach to, and notes adults survive out of water "up to 21 days in very wet conditions (such as inside dock/lift pipes)." A cradle that spends the summer submerged needs scraping in fall; methods that spare bunk carpet and coatings are in boat lift cleaning.
Swimmers
A lowered cradle is a steel or aluminum frame a foot or two under the surface, next to a dock where people jump in. ShoreMaster's instructions tell owners to warn swimmers "of the lift's location when the boat is not present and the lift is hidden under the water," and to "raise the lift rack out of the water after departing to allow swimmers to see the location of the lift."
Cables
Lowering the cradle pays cable off the drum, and on many lifts that puts the lower runs and the cradle sheaves in the water for as long as the lift stays down. ShoreMaster's 2023 maintenance article, in its section on cables, tells owners to "keep your lift raised out of the water when it's not in use to prevent it from wearing out." Raised, most of the cable is wound on the drum above the water and dries between uses.
The case for down, and when it wins
When the lift cannot clear the waves
Up only helps if it is up far enough. FLOE's manual puts it as a rule: "The main cradle lift beams should never act as a wave-break. Make sure that the cradle lift platform is always either raised high enough so that the waves pass under it, or lowered completely beneath the water. Waves breaking against the cradle lift beam will cause unnecessary wear on the lift's frame." The bad position is the middle one, with the beams at the surface taking every wake broadside.
So if high water or a short lift leaves the raised beams in the chop, the answer is down, all the way, to the bottom limit. Stop there rather than driving the cradle onto the lake bed: a cradle resting on the bottom lets the cables go slack, and slack cable is the usual start of overlapping wraps on the drum (see boat lift cable problems).
Worked example: is "up" high enough on your lift?
A vertical lift on a busy lake raises its cradle beams to 20 in above the water at the summer level. Boat Lift Lab's wave allowance for a raised hull on a lake with wake traffic is 18 to 24 in (from water depth requirements), and the same allowance applies to the underside of an empty cradle. At 20 in the beams clear ordinary wakes: leave it up.
In a wet spring the lake runs 12 in higher. The same lift now tops out with the beams 20 - 12 = 8 in above the water, and every passing wake slaps them. Here the lift goes fully down until the lake drops back below about 20 - 18 = 2 in above the summer level, then back up.
Your own number: raise the empty lift to the top and measure from the water to the underside of the lowest cradle beam, then compare it with the wakes your dock actually sees.
Hydraulic lifts over the off-season
Two hydraulic lift makers point the other way once the season ends. ShoreMaster: "Store the lift in the down position over the off-season to protect the hydraulic rams." Pier Pleasure, whose pump box is designed to be disconnected and stored for the off-season: "There will be pressure in hydraulic hoses when the lift is in the raised position. Lower the lift completely to remove the pressure." In season, Pier Pleasure tells owners to fit the lock pin when the lift is not in use, because "hydraulic fluid from the cylinder may flow slowly back into the fluid tank" and the lift can lower on its own. An empty hydraulic lift left up without its pin may not stay up; if yours creeps down with no boat on it, the diagnosis is in hydraulic lift problems.
This is where the confusion has a printed source. ShoreMaster's fall storage blog says to "store your lift with the cradle or platform up, especially if you have a hydraulic hoist or winch system." That line sits in a winterizing article that calls removing the lift from the water the first step. ShoreMaster's hydraulic lift instructions are the document written for that product, and they say down. Where a blog and the manual for your lift disagree, follow the manual.
Working on the winch
ShoreStation's hoist manual: "If you choose to remove the winch cover and inspect or work on the winch, be sure the platform is completely lowered." A raised empty cradle is held by the brake, and the brake is part of what you are working on. Lower it, do the job, and raise it again when the cover is back on.
Wind, canopies and storms
An empty lift with a canopy is a sail with no ballast. Sunstream's canopy manual is blunt: "High wind can actually move your boatlift if you have a canopy cover with no boat on the lift and the canopy is not attached to the dock," and "your boat must be on the lift during high winds or the canopy needs to be attached to the dock." FLOE's lift manual says that if the lift "will be left without a boat on it for any extended amount of time, the canopy fabric should be removed to reduce the possibility of wind damage." Neither manual makes cradle height the fix. Frame and fabric choices are in boat lift canopies.
Hurricanes are a separate decision with its own trade-offs: raising an empty cradle lets debris pass under it, while lowering it keeps surge from lifting and slamming it on its cables. Which one fits your site is worked through in hurricane preparation. Whatever height you choose, switch the power off: Lake Lifter's motor manual says to unplug or turn off the unit when not in use because "lightning and electrical surges can cause unattended operation" (more in lightning and surge protection).
Winter: position will not save a lift from ice
In freezing water the up or down question mostly disappears, because the lift comes out. ShoreMaster's hydraulic instructions: "If your waterway freezes during the winter, you will need to remove your lift, as it will be damaged by ice flows." Pier Pleasure says not to leave its products in the water during winter months. Lifts that stay in, on pilings or in a boathouse, need ice kept off the structure; see winterizing a boat lift. Getting a free-standing lift out and stored is in seasonal lift removal.
The decision in one table
| Situation | Cradle | Also do |
|---|---|---|
| Boat out for the day or week, beams clear the waves when raised | Fully up | Power off; lock pin in on hydraulic lifts that have one |
| High water or short travel, raised beams still in the waves | Fully down, to the bottom limit | Warn swimmers; raise it again when the water drops |
| Hydraulic lift, off-season, staying in unfrozen water | Down, per the manual | Disconnect and store the pump box if designed for it |
| Servicing the winch or brake | Completely lowered | Power locked out |
| Canopy, boat away for an extended time | Up, as above | Remove the canopy fabric |
| Hurricane forecast | Per your storm plan | See hurricane preparation; fabric off, power off |
| Water will freeze | Lift removed, unless built to stay in | Winterize; de-icing where the lift stays |
Where this answer stops applying
- Your lift's manual says otherwise. Follow it. The table above reports eight documents; it does not overrule the one written for your lift.
- Salt and brackish water make the corrosion reason stronger, not weaker. FLOE notes its lifts have not been tested in brackish or salt water at all.
- A boat on the lift is a different question: drive and plug positions are in outboard up or down on a boat lift and drain plug in or out.
Frequently asked questions
Should I leave my boat lift up or down when the boat is not on it?
Up, with the cradle beams raised above the waves, during the boating season. DECO, Davit Master and ShoreMaster all say to raise the empty cradle out of the water, to limit corrosion and slime and so swimmers can see the lift. Lower it fully only if the raised beams would still be hit by waves, for winch service, or for off-season storage of a hydraulic lift.
Is it bad to leave a boat lift in the water?
Leaving the lift structure in unfrozen water is normal. Leaving the empty cradle submerged is what makers advise against: DECO says never leave the lower cradle in the water because electrolysis can cause structural damage, and Davit Master says prolonged submersion promotes deterioration and electrolysis. In water that freezes, ShoreMaster and Pier Pleasure say to remove the lift entirely.
Should a hydraulic boat lift be stored up or down?
Down over the off-season. ShoreMaster's hydraulic lift instructions say to store the lift in the down position to protect the hydraulic rams, and Pier Pleasure says to lower it completely to relieve hose pressure before disconnecting the pump box. In season, leave it up with the lock pin in, because fluid can slowly return to the tank and let an unpinned lift creep down.
Should I take the canopy cover off if the lift is empty?
If the boat will be away for an extended time, yes. FLOE's manual says to remove the fabric to reduce the chance of wind damage, and Sunstream's canopy manual warns that high wind can move a lift whose canopy has no boat under it and is not attached to the dock. Remove it before winds rise, not during them.
Sources and further reading
- DECO Power Lift RMC, Ultimate Power Lift owner's manual (2025): Things to NEVER Do, launching and lifting procedures (https://cdn.prod.website-files.com/6940804465b3401c5de58a83/69e70c71711463e8f1a99ad2_2025%20DECO%20Owners%20Manual.pdf)
- Davit Master, Owners Manual, Vertical Cradle Lifts: launching, work platform and maintenance (https://www.davitmaster.com/pdf/cradle-lifts/CRADLE-OWNERS-MANUAL.pdf)
- ShoreMaster, Hydraulic Boat Lifts, Hydraulic Box Instructions, 4000 lb to 12500 lb capacity (document 1024719): operation, storage and off-season suggestions (https://static.shoremaster.com/instructions/1024719_SMR.pdf)
- FLOE International, Owner's Manual, VSD-3800 and VSD-5000 Boat Lift Systems (500-90108-01): wave-break warning, canopy fabric removal (https://support.floeintl.com/wp-content/uploads/2024/05/500-90108-01-VSD3800-5000_DC.pdf)
- Pier Pleasure, Hydraulic Boat Lift Owner's Manual (2020 to present): lock pin, storage for the off-season, winter warning (https://www.pierpleasure.com/wp-content/uploads/2026/03/owners-manual-hydraulic-lifts-2020-present.pdf)
- Sunstream, Canopy Owners Manual (690179 rev C): high wind and canopy removal (https://sunstreamboatlifts.com/wp-content/uploads/2014/05/Canopy-instruction-manual.pdf)
- Midwest Industries (ShoreStation), SS1053 PWC dock mount hoist manual 0004405 rev B, safety precautions (https://www.boatliftanddock.com/MediaStorage/Product/Documents/Document/3715_20220602120213498.pdf)
- ShoreMaster, "How to make your boat lift life last," February 2, 2023 (https://www.shoremaster.com/blog/articles/how-to-make-your-boat-lift-life-last/)
- ShoreMaster, "Fall Boat Lift Storage Tips," October 21, 2021 (https://www.shoremaster.com/blog/articles/fall-boat-lift-storage-tips-shoremaster/)
- Lake Lifter, AC 120v Direct Drive Boat Lift Motor manual (https://www.boatliftanddock.com/MediaStorage/Product/Documents/Document/5699_20231205111029683.pdf)
- Minnesota DNR, Zebra mussel (attachment to boat lifts, survival out of water) (https://www.dnr.state.mn.us/invasives/aquaticanimals/zebramussel/index.html)