• Mobile App For Android Now Online!

    Download it here. The app is searchable in the Google Play Store under Sailboat Owners.

    Sorry iPhone/iPad users, we are still waiting on Apple. :(

    Click the X in the upper right corner to make this go away

How to Clean Mildew from line(rope)

Jan 6, 2010
Catalina 30 Mark II John's Pass Florida
My traveler line being in the shade of a wet winter is showing green mildew on the dress end loops. I know that I can soak it in bleach, however that beats up the chord.

Has anyone with similar problems found a better cleaning method to do this?


Nov 18, 2013
Oday 32 Ketch North Fort Myers, FL
When I purchased our Oday in October 13, everything had green mildew and
black mold throughout. Deck surfaces, hull areas with mold, headliner and hidden spots in the cabin were treated with bleach, purple power and dawn liquid. Worked like magic. When I got the price for replacement of all the running rigging, I figured I could bring back most of the halyards and sheets to usefulness if I could remove the black and green accumulation they had grown. Using water with a liberal dose of Dawn liquid and approx. 4 tablespoons bleach per gallon (don't use too much), I soaked the lines for about three hours, periodically agitating them in the bucket about hourly. I immediately rinsed them very thoroughly in fresh water and rereigged them. The mainsheet, preventer, and three halyards at the main came beautifully clean and were soft enough to hand to be used and showed no signs of damage to the lines. The mizzen sheet was the first line I attempted to clean and the amount of bleach I used was considerably stronger in solution than I used later. The mizzen sheet came clean but the outer cover shredded and came apart as I rinsed it. Use sparing amounts of bleach and you should be fine. I think I saved about 600 dollars cleaning lines instead of replacing them.
Good luck,

Dec 2, 1999
Hunter Vision-36 Rio Vista, CA.
When I wash lines I ALWAYS put them in a pillow case or a bag that can be closed. This allows the soap/water/bleach etc to get into the line without beating them to death. Once they are washed & rinsed just remove them and let them air dry.
Oct 30, 2011
klidescope 30t norfolk

I wash my running rigging every year even the shackle ended main halyard in a laundry bag (mesh bag) at the local laundry mat , a little bleach and lot of fabric softener then air dry gonna try some Rit Dye this year on the red ( port ) jib sheet to try to put color back might turn it pink though
Jul 1, 1998
Hunter Legend 35 Poulsbo/Semiahmoo WA
Use messenger lines on halyards & topping lift

To keep the lines looking as "fresh" as possible, and we get a LOT of rain here, I've been attaching messenger lines on the halyards and topping lift then running them to the top of the mast and tying the messenger lines off someplace on the boat - pulpit or pushpit.

The halyards and topping lift are all internal in the mast so only the part from where they exit the base of the mast then go aft to the rope clutches are exposed. The exposed area is covered with a tarp and a piece of wood is placed under the lines to keep them off the deck. Replacing the tarp with a Sunbrella cover is on the to-do list. (Been there for several years)

In the case of the power cord that runs from the bow to the cockpit, I tie it off on the top lifeline to keep it off the deck.

The main sheet is removed from the boom and covered by the same tarp that is covering the mast lines going aft.

All these lines, even though several are older, still look reasonably "fresh".

The line on the front of the mast for the spinaker pole car I've never figured out a way to protect it so it doesn't look too good.

Oh, and the furler swivel is covered in plastic to keep the sun and dirt at bay. Replaced the bearings a few years ago and it works much smoother now.

The devil is in the details: One thing I will say is the 1/4" messenger lines are not all created equal. Some I bought two years ago didn't even last a year (braided) and kinda turned to powder while another one (stranded) is probably more than 20 years old. Use the best line on the main halyard just in case one of the others fail and you have to go up the mast. Better yet, keep track of where you bought them, keep the receipt and the bag they came in, just in case there is a premature aging problem. The ones that went bad last year came from either Home Depot or Coast Do it Best Hardware.

Prevention is the best medicine.
Jun 2, 2013
Catalina 27 Vancouver
The '72 Catalina 27' I bought last year had very dirty and moldy lines throughout. I've had very good results cleaning them. My process is to soak them for 24-48 hrs in our spare bathtub using, wait for it... Shampoo. I find it does a terrific job of eating through the grease and dirt and dislodging the green mold. Periodic massage and I do use a couple capfuls of bleach for the worst ones, but avoid if at all possible. After their spa treatment, I daisy chain them and wash them on gentle cycle (no spin) inside an old cloth pillow case, and hang to dry. They look fantastic, and come out very soft on the hands. I even did my anchor rode this way, which was deeply stained with mud from the muddy bottoms we have around Vancouver. It's not perfectly white but looks way better and easier to handle. Proof it works is I have even been able to put new eye splices in after washing, something they say is almost impossible on old lines. Plus my wife likes the way they smell! ; )
Jan 19, 2010
Hunter 26 Charleston
I wash my running rigging every year even the shackle ended main halyard in a laundry bag (mesh bag) at the local laundry mat , a little bleach and lot of fabric softener then air dry gonna try some Rit Dye this year on the red ( port ) jib sheet to try to put color back might turn it pink though

Dito: And I will periodically do all of my cushion covers this way. I've even used my own washing machine for line and covers. Just set the wash to "gentle/handwash'.

I've also washed sails in a new (clean) garbage can by soaking the sails in woolite. Then spraying with a hose.
Mar 26, 2011
Corsair F-24 MK I Deale, MD
Replace lines because of mildew? Really? Bleach them and weaken them 10-20%, depending on the circumstances and cycles (I ran the PS tests)? Really?

Washing them will extend life (solids wear them down, numerous good suggestions above). Water reppelant treatments like Nikwax Rope Proof or TX Dirrect will extend life and help them run better (improve internal lubrication). Don't use a power washer.

It's a boat, not the dining room table.
Jan 6, 2010
Catalina 30 Mark II John's Pass Florida

Thanks, there ware a lot of good suggestions here.
I first thought of using some bleach with a cleaner but, I didn't have a warm fuzzy feeling about this. As in my water tanks, I use pool chlorine as it smells better & not as harsh.

I did like the link TeD supplied. It was very thorough on do's & don'ts for cleaning lines.
This is the first year my boom sheet turned green. It's been a wet foggy winter.

Time to get a bucket, mild detergent & soak it for a few days.

Thanks to all......



Sep 13, 2012
1979 Hunter Cherubini 30 Clemmons
Don't use a power washer
I got to admit when I got my project boat the mast and halyards were laying on the ground. The lines were green and dirty and looked like they were ready for the garbage can. I laid each one on top of the mast and sprayed them down with my 1600 psi pressure washer at about 12". They look darn near new now. I wouldn't blast them with 2750 psi at 3 inches but a low powered washer did the trick on mine with no damage. Just wondering what your comment on not using a pressure washer is based on.