Leaking hydralic backstay tensioner, removing?

[Bob666]

Hi!

We have a masthead sailing boat.
NORLIN 37 sailboat specifications and details on sailboatdata.com

We are planning ARC, currently refitting her.

The backstay has a hydraulic backstay tensioner (fitted by previous owner who did some competing). It begun leaking oil recently.

If all oil leaks out, will we loose the rigging? Or what will happen?

We want things to adhere to KISS and willingly sacrifice fancy features to take that path. Should we get rid of it altogether rather than repairing it?

Also, considering fitting another backstay. Good idea? If we do so, should the inner one (5 cm lower at masthead) be a bit slack so you basically only use one of the backstays while the other one is just for rendunancy, as a failover?

The Norlin 37 also has inner forestay. When going against the wind in heavy weather, we fit a babystay and two barduns/runners, to avoid the mast to pump back and forth. So maybe we shouldn't need two backstays after all?

She was after all constructed for offshore sailing, why we chose her in the first place. I realise that still means upgrading needs to be done, but anyway...

Thanks,

[exMaggieDrum]

My backstay hydraulic adjuster has a very small slow leak. I need to take it off and rebuild it or have it rebuilt. I'll have to put a temporary backstay to keep the mast on, or at least I'll feel better if I do. I may get a rigger to help, or not, if I find out enough to be comfortable doing it myself. The leak is so small it isn't very high on my list yet.

[SoundOfSilence]

My hydraulic backstay is also leaking. I have found the leakage to be inside the steering pedestal where the control is mounted. It's almost on top of the "to do" list and hopefully it will only be to tighten something to get rid of the leakage. I would suggest you to find out where it's leaking before you throw it away, maybe it's very simple to sort out?

If you have 2x running backstays, you shouldn't need another backstay. Do you also have a boom topping lift, which you can use in case of problems with the backstay?

How old is your rigging?

[Bob666]

Hi!

What an excellent forum this is!

I hope running backstays = bardun. Google translate didn't know. "Rune" makes me suspect you speak a Scandinavian language as well? I could be wrong.

The Norlin 37 has a fat mast and solid rigging so I'd rather not fit another backstay unless I must.

The boat is from 1974. The mast is original but all rigging was replaced during approx 2004-2016. We bought her 2016.

How would a boom topping lift ("dirk"?) help if the backstay fails? Anyway, we don't have that. We have jackstays.

I'm considering removing the hydraulic altogether. We will remove the mast this winter so might as well...?

We're a bit hardcore when it comes to adhering to KISS.

Cheers

[barnakiel]

I cannot speak for what tensioner you have there but most common navtec ones just stop at the extreme position if you lose all oil. Just open it up all the way and you will see where it stops and if it does introduce any free play in the rigging. There should be no slack.

If there is slack then your backstay or forestay wire are too long. The tensioner is there to adjust tension in an already pre-tensioned system, NOT to create tension in a slack system. With all oil out, you should be at plain tune hence 100% safe to sail the boat (just unable temporarily to create extra forestay tension required when racing upwind in moderate condition).

Keep the rigging as it was. Do not modify stuff or else risk breaking the stick.

If you have any doubts about your tensioner, you can remove it and fit a regular turnbuckle.

Cheers,
b.

[roverhi]

You can either have the backstaytensioner rebuilt and hopefully cure the leak or fit a new backstay without the tensioner. It's your call though I like the ability to adjust headstay tension easily with my mechanical backstay adjuster. A boat leaving SF Bay on a cruise had the hydraulic backstay tensioner blow a seal in the potato patch outside the Bay. They did not lose the stick but the masthead whipping about with the suddenly slack backstay caused a bit of excitement. IIRC, they turned around, had the tensioner rebuilt and continued on.

With running backstays see no reason for dual backstays. You can limp into port using a reefed main and staysail and possibly even replace the offending stay at sea if you carry spare wire and terminals.

[SoundOfSilence]

Yes, I'm Norwegian

I found a picture of "running backstays", see below. I'm not sure what "bardun" is. Easy to get confused in all these expressions. On Herminia the running backstays are combined with "check stays". This gives excellent support on various location of the mast when reefing.



I also found the below picture of a "boom topping lift". If you have problems with the backstay and the mast is still standing, you can just detach it from the boom and attach it to the same place as the backstay is attached and use it temporarily as a backstay to stabilize the mast.

[Bleemus]

Nav tech hydraulic back stay adjusters are easy to rebuild and not expensive to have someone do it for you. Put a halyard to the stern. Remove the Navtec and bring it to a shop.

[phorvati]

It will just leak more an more, but I would take care of it before ARC. hydraulic shops will rebuild them. My Hydra II is so old that it took them a while to figure it out. Im a DIY, rebuilt diesels and gasoline engines before as well as build my on refrigeration, but this tensioner is one of those things that I never took seriously enough or put the effort to grasp that the dam thing is pretty complex and important. So i take it to the shop. In fact twice in the last 13 years.

[barnakiel]

The repair is straightforward. It is either the gasket (common) or else the nipple/racor. Your local garage will do this in less than 24 hours, if they have the part in stock or available locally. (Almost certain if you live close to Stockholm or Goteborg).

Older tensioners at time require odd gaskets so allow time for your hydraulics shops to source and order one, if you have anything pre-90 or thereabouts.

You cannot use runners to secure a mast with a slack backstay, the top will flop, bend, and you will lose the forestay and the furler. Except if the runners run very high up, in which case they are not required (two forestays spaced vertically less than % of the unsupported column).

But as I said, there should not be any slack with the tensioner empty and all way out. Unless someone tried to kill two birds with one stone and used the tensioner for building the right pre-tension. But this assumes an owners error so let's not assume too much.

I hope the images are self explanatory in respect of which part is used to make the rig tight and which part is used for the extra tension required while racing / beating.

http://cdn6.bigcommerce.com/s-aw5q7t...0.1280.jpg?c=2

http://hallberg-rassy46.com/imprompt...1/img_2850.jpg

Cheers,
b.

[donradcliffe]

The benefits of your backstay tensioner are that you can release the pressure on the rigging and the hull when you are not sailing, and adjust it when you are sailing. Tightening the tensioner takes sag out of the forestay, reducing the draft of the jib and allowing sailing higher into the wind. It also tends to bend the mast, which allows you to control the mainsail shape with your running backs and checkstays.

If you lose all your hydraulic fluid, the forestay will sag more, but there is a stop in the tensioner, and you are little danger of losing the mast. My tensioner started to leak coming across the Indian Ocean, so I replaced it with a turnbuckle and spare rigging bits I had on board. I couldn't get the tension I wanted with the turnbuckle, so I sailed up the Red Sea with a sagging forestay and had the tensioner rebuilt in the Med.

Hard on the wind, the tensioner will improve your daily mileage, but most of the ARC is off the wind, where the tensioner is not really needed.

If it was my boat, I would have the tensioner rebuilt before I left on a passage.

[barnakiel]

Originally Posted by SoundOfSilence

I found a picture of "running backstays", see below. I'm not sure what "bardun" is. Easy to get confused in all these expressions.

I think it is just like the Dutch word pardoen - basically a part used to (counter/) support the load from the inner forestay (/-s). However, it does not run aft to the blocks and winches (it is not 'running') but is rather fixed to the deck (-plate) just aft of the aft lower.

I do not know the English word, maybe someone can chime in.

So basically a 'non-running runner'. Or a tall shroud that meets the inner forestay then meets the deck just aft of the lower stay.

None of which can be used to support the top of the mast, should the backstay go South.

As you noted, the topping lift (if built very strong) can be used temporarily. This should not be required if the main is up. Just hoist it in full and tension its sheet - the sail, the toplift and the sheets will hold the top somewhat protected while one fumbles sorting out any backstay challenges. Tension the lift then, just to avoid stretching the leech.

Cheers,
b.

[exMaggieDrum]

Thanks for all the good posts on this. I will remove and get my tensioner rebuilt (or replace if necessary - I hope not). I think my running back stays can keep the mast up while at dock while the repair is made. I like having the tensioner too. I certainly would get it fixed before I go offshore next.

[barnakiel]

When removing a tensioner (or any other part of the rigging), always remove the tension from the counter-balancing wire as well. A bit here and a bit there. Till there is no tension. Secure the freed part with extra lines (halyards, etc).

As long as the mast is in column and secured, you are fine.

b.

[Basil]

Hi I had a similar problem an lost all oil from unit, but the unit held together, and supported the now very slack back stay, I used running back stays an a block to the primary winch to support the mast ( an roller furling unit) an then removed the hydrolic unit. I then had a short length of " back stay " with a bottle screw at the base to replace the unit.This way I have ensured that I do not have this problem again, happy to send photos of the new set up.