Wednesday, March 1, 2023

Lewmar Ocean Electric Winch Installation

The Pan Oceanic 46 models built in Taiwan came with manual Barient 32 primary and Barient 26 secondary winches. When looking at replacing the winches we decided to upgrade to some newer Lewmar Ocean winches.  The Pan Oceanic has a cutter rig so the headsails are not that big. The original two speed Barient 32 primary winches were somewhat oversized. 

Sizing a Winch


Adding winches to a sailboat is based on the size of the load the sail will exert on the winch.  Most winch manufacturers provide graphs and tables to determine roughly what size of a winch should be used on various sized sailboats and wind loadings. 

Loading will differ depending if the winch is being used as a primary headsail, staysail or mainsail application. The largest load on the winch will most likely come from the genoa or head sail.  Searching the internet I found some calculations for determining wind force based on the sail area.

Wind pressure per square foot equals .00256 x wind speed in mph squared. This means that the force on the sail is magnified by the square of the wind speed.

SL = SA x V2 x 0.00431

SL = Sheet loading in lbs

SA = Sail Area in square ft

V = Wind speed in knots

Wildthing has a cutter rig so the headsail is only 550 square ft. We will use 30 knots as the maximum wind speed. The genoa will most likely be reefed prior to 30 knots so the wind speed will be for worst case.

SL = 550 x 30sq x 0.00431

SL = 2133 lbs

Lewmar provides the table below to roughly size the winch based on the boats length and sail area size. To more accurately size the winch the specific winch safe working load (SWL) should be determined. The instruction manual for the Lewmar winches show the SWL of the various electric winches as shown below. 

Lewmar Ocean 46 SWL = 2645 lbs/ 1200 kg

Lewmar Ocean 48 SWL = 2756 lbs/ 1250 kg

Lewmar Ocean 50 SWL = 3000 lbs/ 1360 kg

The graph below shows for a 46 foot sailboat we would need a winch size of 55 at a minimum. Looking at the sail size of 550 square feet shows we need a minimum size of a 45. A Lewmar Ocean 46 would have possibly worked but we selected a Lewmar Ocean 48, the next size up, for a safety margin of 22%. Both of these sizes were available on the used market.  

So the selection of the Lewmar Ocean 48 (SWL 2756 lbs) should be large enough to handle the 550 square foot genoa loading of 2133lbs.


New Winches vs Used

We wanted to add primary electric winches for the genoa to make the boat easier to handle. The secondary winches for the much smaller stay sail would remain manual. The price of new winches is astronomical so we started to look at the used market.  If  you know me, I like a deal! 

The best place to find used winches is on eBay. We had time to shop around which made it easier to look for some good used winches. Parts for winches are readily available also so buying used winches that may need bearings or gears is not an issue. Buying used winches we saved over 50% from the price of purchasing new winches. New electric Lewmar Ocean 48 winches are about $5000 a piece. Conversion kits for manual winches to electric of this size run near $2000. We found Lewmar Ocean 48s with motors for about $1500-1800 a piece. The manual Lewmar Ocean 46's were picked up for $500-600 a piece. 

Electric Conversion


Converting Lewmar winches to electric can be done for sizes 40 and larger. Lewmar winches older than 2000 cannot be converted to electric. Conversion kits are readily available at most marine stores. The cost of the conversion kits are often as expensive as the winch itself. 

The kits consist of a new base plate, a drive unit, gear box, contactor, circuit breaker and switch. I did not purchase the kits as they are almost as much as buying a new winch.

I was able to purchase one electric Lewmar Ocean 48 with a 700 watt electric motor on eBay for $1500. I also purchased an electric Lewmar Ocean 46 with a 1500 watt motor for $1800. The plan was to convert the 46 into a manual winch and use the motor to power a Lewmar 48.

I waited a few months and sure enough another manual 2 speed Lewmar 48 came available for $600.  The drive shaft for the 46 and 48 are the same so I could reuse that and the motor to drive the 48. The other item I needed was the electric winch base with the bearing.  I found one of those on eBay for $150 in Great Britain. That arrived in a few weeks so my plan was coming together.

Installation

Installing the electric winches required that a large 2 1/2 inch whole be cut in the deck for the drive shaft and electric motor to attach below deck. The Pan Oceanics have a large slanted winch bases built on the bullworks in the cockpit. We followed the Lewmar winch installation guide to make sure we oriented the winch main drive gear towards the back of the winch to take the maximum load. The winch motor can be oriented in one of 4 positions below deck at 90 degree increments. Make sure to measure twice and cut once! 

We pulled off the old winches, filled the holes and drilled new holes to mount the winch bases. Lewmar suggest that the main drive gear of the winch be mounted in line with sheet lines. 

We oriented the winch base and made sure we had room below deck for the drive motors and gearbox. We ended up cutting out some of bulkheads in the cockpit lockers to make room for the motors. 

We used butyl rubber on the deck plate to waterproof the installation.



This is one of the Lewmar Ocean 48s. The motor and drive unit are on the right. The four bolts are used to connect it to the winch drive base below deck. The drive shaft is keyed and goes into the middle of the motor drive unit. 

The winches are mounted and the gears and bell housing are attached above deck.


The port side Lewmar two speed manual winch

Starboard side winches installed


I wired the winches on one 12 volt circuit which is powered from the house bank batteries. I used 2/0 tinned marine cable to power the winches. The circuit runs through a 300 amp shut off switch and is protected by a Blue Seas 150 amp circuit breaker.

I put both winches on the same circuit. This means I can only run one winch at a time. If I run both winches at the same time the current draw on the circuit could exceed the 150 amps and trip the circuit breaker.  I chose to do it this way to reduce the cabling expense and installation cost. 2/0 cable runs about $6-$9 dollars a foot so it is a big cost of the installation.  I expect to only use one winch at a time while sailing so having both on one circuit should not be an issue. Make sure to size your cable according to the winch manufacturers recommendations. The length of the cable runs will also affect the sizing of the cable.

I used two separate contactors and switches to operate the winches. I purchased one Lewmar Type E contactor for about $90. This is a simple contractor which operates the winch in one direction. It is basically a solenoid with some added thermal overload protection.

The contactors are wired in the positive circuit of the 2/0 cable. The contactors are operated by push button switches mounted on each side of  the cockpit combing. 

 


This shows the cabling coming out from under the cockpit to the port side winch. The positive, red conductor was put in plastic conduit to prevent any damage or short circuits. 
This shows the port motor with the positive and negative connections.
For one of the winches I decided to try something a little different. Instead of buying another Lewmar Type E contactor. I purchased a winch solenoid on Amazon for only $19.00.

This solenoid is normally used for a winch on an ATV and allows it to run the winch in and out. I only needed it to operate in one direction so you can see that only the right two terminals were used. It has a 500 amp rating so it is more than enough capacity to run the 1500 watt motor continuously. This solenoid is similar to the one we have on the electric anchor windlass.

The red cable from the house bank batteries comes in on the right side. When the winch button is pushed the power comes out the left side to drive the starboard winch. The other red conductor goes over to the port side to power the Lewmar contactor.
To operate the winches I used these new momentary, lighted, waterproof, stainless steel low profile switches by Apiele. I looked at buying the Lewmar winch switches but they were $90 each. These switches had a 10 amp rating and were $15 each on Amazon. These switches are becoming very popular and are used on many new boats in the marine industry. 

https://www.amazon.com/APIELE-warranty-Momentary-Waterproof-Stainless/dp/B07ZB2QZKS?ref_=ast_sto_dp&th=1&psc=1





I think the installation of the new electric winches will make this big 46 footer easier to sail. If I was 20 years old manual winches would have worked fine. Since I am now in my 60s anything we can do to make it easier to sail is a welcomed addition. It was a do it yourselfer installation using some non standard parts and equipment. It was a challenge to source all the parts and make it all work but it was satisfying to see it come together. Total purchase price of the installation of the four winches was about $5500. This was about the price of just one new Lewmar electric 48 so it was worth it.  I hope you found this helpful.




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