Navtec Backstay adjuster problem Ericson 35-3

david poth

Member I
Hello All,
I have a Navtec hydraulic Backstay adjuster on our 35-3 that I would like to eliminate. It leaks and does not hold pressure. I would like something simple or eliminate an adjuster all together. Wondering what the options are.
David Poth
Ericsson 35-3 1985


Sustaining Member
Hi David,

The Navtec seals can be rebuilt but it's at least a few hundred dollars and I'm not sure if it's a job that requires a professional rigger and special tools, but I've never replaced the seals myself. I've had mine rebuilt TWICE in 12 years. My seals were shot when I bought my boat so I'll say mine didn't last 10 years in MD out in the sun all year. I've read that keeping the sun and dirt/debris off the top rod seal with a cover should help prolong the life of the seal - but I haven't mad a cover yet.

The Navtec is good for fairly quick adjustments which is what a racer wants. Other options are: current racing practice is a cascading series of blocks providing LARGE mechanical advantage - at least 24:1 for us. This is simplier and lighter than the hydraulic backstay adjuster and the adjustments can be made even faster, so the backstay tension can be played while racing. You'll need high quality blocks and high tech, no stretch line to make this conversion. The line will wear out eventually and need to be replaced, The blocks should last a long time.

If you're not racing and just want to make adjustments each day or once a day for sailing conditions there are several mechanical adjusters that are ideal for this use. I've seen adjustable turnbuckles with wheels and also ones with fold out levers that seem perfect for this use. Other EY.o members should be able to recommend specific models.

If you really never adjust your backstay and don't desire to, you can remove the Navtec and substitute a standard rigging turnbuckle that you would adjust when the rig goes up and lock with cotter pins just like the side shrouds.


david poth

Member I
Thanks Mark. I’m leaning toward removing it and making it permanent. I know the racers hate that idea, I have gotten mixed opinions. It seems that there is not as much benefit to have it with a masthead sloop. Either way I’m getting rid of the hydraulics.

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
1) Having the ability to quickly load and unload the backstay (and therefore the forestay) is a good thing for all sailing, and has nothing to do with "racing" per se. But you know that. It does have a lot to do with sailing to windward.
2) Navtec adjusters may or may not be in production any more. I thought that after Lewmar bought them, they later discontinued them, but am not sure.
3) EY installed them on their 80's boats, along with the Olsons.
4) After having our original Navtec unit rebuilt once, and having it again fail to hold pressure a few years later, we replaced it with a "SailTec" unit. Still working fine.
5) A friend of mine with an E-32-3, replaced his with a winch-handle-operated mechanical adjuster. Might have been from Wichard. Not fast to adjust, but it works and is 'simlple' in concept.

Edit: I wonder if a failure to hold pressure might be remedied for your brand as it was one time for ours?
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david poth

Member I
Thank you Loren
Now I’m leaning more toward a non hydraulic adjuster and getting a manual adjuster. I see some with a wheel and some with folding handles. I haven’t seen any with winch a handle. I agree with you it’s good for all sailing.
thank you


Member I
I had my seals replaced professionally and could have gone to any truck centr or hydraulic shop and had done cheaper.I went to a truck/ heavy equipment shop last summer and they made a new 8ft line for me with the fittings for 100 bucks Canadian.So happy with Genoa looking proper.


NavTech is still around in Mystic CT. they have a flat rate rebuild. I believe it is up to 850.00
The original Company closed and I believe they were taken over by the employees.

Mark F

Contributing Partner
Blogs Author
I replaced a simple turnbuckle on my E27 with a ratcheting backstay adjuster that I found on eBay. I don't know the brand. It is a slow process to adjust but it is simple and it works.


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