Air pressure in Navtec Boomvang

[magique]

I am having problems with my hydraulic boom vang on my 1987 44 sail boat . the vang is original equipment and was manufactured by navtec. no problem with pumping the boom down . when we drop the main , it drops on to the top of the bimini . no pressure there to hold it up . we took it to the local Linde gas company to have the 600 psi of nitrogen pumped in , however it leaked right back out through the screw cap fitting at the end where we pumped it in. We are in Curacao so there are no navtec dealers anywhere near us . Took it to a reputable local machine shop to have the seal replaced in the air input chamber .they cannot get it apart to do this . Does anybody have any ideas on how to take apart or install a new seal for the air end of the vang ? I have emailed navtec several times without receiving an answer to my email .

[a64pilot]

I don't know anything about a Navtec boom vang
But Oleo struts are very common in aircraft, they are of course air over hydraulic shock absorbers, with the air or nitrogen being the spring.
It's possible they may use the same valve is why a picture may help, often manufacturers of course buy what is commonly available, and maybe the valve is the same?

[GordMay]

See ➥ http://www.cruisersforum.com/forums/...king-8657.html

No agent listed in Curacao, but several throughout Caribbean ➥ http://www.navtecriggingsolutions.co...ts--world.html

[magique]

yes I am aware of all the dealers in the Eastern Caribbean ,however my plans are not to head east but west to Columbia . Seems like a huge waste of time to head back east for a simple little fix that I could probably have done here if Navtec would just offer a little advice rather that telling me that I must ship it to the Eastern Caribbean . I have taken it to a very reputable machine shop here in Curacao . The problem is just with one seal , the one that is where you put the air or nitrogen in to the unit . When you fill it up and put the screw cap back on ,it leaks out around the cap . should not be to complicated to fix. The cost to ship it to another island would be atrocious .

[a64pilot]

This is leaking from the fitting used to charge the cylinder, and not the cylinder seals themselves?
Does this fitting look a lot like a tire schader valve, except that is does not have the little needle in the middle?
Does it have like a 5/8" nut at the bottom of the stem? If so then this nut is loosened to allow nitrogen or air into the strut, and every accumulator I have serviced has an O ring for this valve.

Does it look like this?
http://www.hydrofitting.com/prod_ima...ing_valves.jpg

[Stumble]

You can blame Navtec all you want, but those things are under enormous preassure, it's pretty reasonable they don't want people who don't work on them regularly to mess with them. Without the right tools dealing with compression springs can be very difficult if not impossible.

Sometimes when manufacturers say some repair isn't for DIY they have very good reasons for it.

[magique]

Yes I am talking about the seal that stops the nitrogen from coming out after you have finished filling it and before you put the threaded nut back in that has a slotted screw head.
And to the second post , I am not DYI ing this job , I have a hired the local reputable machine shop that has loads of experience working on gas loaded struts ,etc. Probably would know more about this type of thing than the authorized dealer on one of the islands in the Eastern Caribbean ,judging by my ten years of experience cruising the Caribbean islands.

[Banshe]

I have a Navtec 10-1 which collapsed as you described. I was in the Caribbean when it happened. I phoned Navtec and they said the best man to fix it is Brian Evens at Rig Pro. Unfortunately he is in Portsmouth RI. I sailed there and he put a new kit into it and recharged the gas. He did an excellent job. Perhaps you may like to contact him. Mobile +1 4016481735. brian.evans@southernspars.com

James

[magique]

Thank you for the contact information , I shall email him .

[Silver_Surfer]

I just called them about their hyd backstay and vang Give them a call
+1 (203) 458-3163
The tech support is pretty good.


Sent from my iPhone using Cruisers Sailing Forum

[Banshe]

You're welcome.
I recall him saying the problem with mine was that the main plunger seal within had blown allowing the gas to escape. Maybe that's your problem too. I don't think it's the external valve. I would say you will need to install a whole new seal kit. The hydraulic side on mine was was still working OK even without gas. Also I remember him saying that there must be a small quantity of oil to be added to the gas cylinder so it will sit against the seal so the gas is isolated from the seal to stop it leaking.
I don't know where You'd get a kit. Maybe online?

James

[magique]

Yes the hydraulic side is still working fine , just the problem with the boom not staying up . The problem right now is for the machine shop here to find the right tool to access the seal and then as you say find the proper seal kit. Thanks again.

[UNCIVILIZED]

There are other manufacturers of sailboat hydraulics, so it might be worth talking to them, in order to get some more information/gain some insight.

Also, were it me, I'd also post this over on Sailing Anarchy Forums given that there are a Lof of racers there, with plenty of experience with both Navtec, & Hydraulics. Including sailboat hydraulics of other makes.Plus, there may be some resources on www.L-36.com as well.

And it couldn't hurt to contact some of the bigger rig shops in the US either. For more info, possibly parts, & if you're lucky, the POC for a local who can fix it for you.
Florida Rigging & Hydraulics comes to mind, but I'm a bit under-caffeinated at the moment. So the name may be a touch off. But there are some Huge rigging outfits in FL, so it's worth a shot.

In the meantime, in order to keep the boom from being a head knocker, you can take a block of softwood. As in only one notch more dent resistant than Balsa. And drill it, longitudinally, so that the hole's slightly bigger than your vang's piston. Then saw it down the middle, & put it in place with a couple of lashings.

Just be sure to clean both the block & the cylinder ever day or three, Religiously. So as not to score the piston. Thus screwing things up royally.
Ah, & put a bevel/recess on the ends of the inside of the hole. So that where it meets the vang's cylinder, naught comes anywhere close to kissing any seals or vital bits.

Or, a better option, is to simply beef up your lazy jacks so that they're strong enough to support the; boom, the sail, & a couple of people hanging on same.
That, or an old fashioned topping lift.

PS: If you go with the block for the lower end of the vang's piston, you might also cut some flutes on it's inside, longitudinally, so as to give what grime does get in there, a way to flow out. In between cleanings that is.

[Banshe]

G'day again,
you can determine the model of your vang by measuring the shaft size and body size.

If the shaft is 3/4" and the body 1.66" then it's a model 10. If the shaft size is 7/8" and body 2" then it's model 12.

The kit you want is probably 'Navtec A850' It comes with full explicit instructions of how to dismantle, replace, and re-assemble the vang.

You may be able to get the instructions on line. Try googleing Navtec A850 or navtec support.

James

[TheThunderbird]

I don't know of anything more sensible than hydraulic gear in a sailing boat.

There are only TWO approved , official and authorized Navtec centers all around Italy....

Nothing is banal about it. Tools are NAVTEC proprietary too, as too many "very reputable" lads screw them up usually.


It is guilty not to revision hydraulics after 12 years, not say 25-30.....
I spent 1850eur to review the unit +3pistons.

All showed evidence of mismanagement, DIY stupidities, incorrect fittings, etc (French PO are the worst....)

It is atrocious to have a similar negligence, not to moan about shipping costs

I hope you get the right people doing it..