Air keel

smokeeater341 · 28 July 2009, 04:24

Hi all,

Been around a while with my Bombard 470 Explorer that I had to sell last year due to storage issues. I recently bought a MK II GR with a 30 Johnson O/B Tiller. I love this boat and have been wiping off the oxidation, prepping the trailer (it wasn't used for quite a while) and generally giving it a good cleaning.

My question is with the air keel. When I disassembled the composite flooring, I noticed that the air keel just sits sandwiched between the hull and the floorboards with no point of securement on the inner floor. Is this the norm with this model of Zodiac? Will it create chafe points? Or shift under load?

The air keel is quite a bit older than the tubes and is quite brittle (ie. the creases from being folded over the years has created weathered cracks on the surface that leak). Can I repair this? Is it worth it? Or should I replace the keel with another one...at a hellishly expensive price. Are there alternatives to an air keel? I talked to a local distributor and he suggested some type of adhesive that seals from the inside, regardless of condition of exterior....a two week turnaround at 10% of the price of replacing it. The exterior material is quite different than the tubes (more like a PVC than a hypalon which I believe the tubes are)

Any suggestions regarding these types of keels and what I should try would be greatly appreciated.

Thanks,

N.

lightning · 28 July 2009, 09:34

I've got a Zodiac 2.85m and it's got the solid floor with an air keel underneath, I assume this is what you mean? A long tube that runs down the centre of the floor and is inflated to produce a V-hull by pushing the bottom of the boat against the floorboards?
Mine is attached to the floor but only by a couple of PVC flaps, one at each end. I imagine that in time these would break.

smokeeater341 · 28 July 2009, 13:53

Hi Lightning,

That is exactly the same keel as I am talking about. The PVC flaps that you speak of are long gone on mine. My major concern is how to try and repair the leak(s) on the air keel. I did a search in here and wondered how much success others have had with a) wood keels b) polystyrene c) latex-filled repairs from the inside.

The quote I got for replacement was @ $1000.00 !!!!

Any opinions on which way I should go with this? The tubes, transom and floor all seem to be in great shape and I really don't want to use an inferior product or process that I will regret down the line.

Thanks again.

lightning · 28 July 2009, 17:41

$1000? Good heavens, that's nearly the cost of a new boat! is that just for the air keel?
It must be possible to do it another way. Your air keel sounds like it's at the end of it's life, have you looked at other boats with a similar air keel to see what they charge for a new one? Honda for instance.

smokeeater341 · 28 July 2009, 18:16

That's exactly what I said to the rep. Zodiac replacement parts aren't cheap, I understand that but this quote was off the radar! I'm in the process of trying other manufacturers to see if I can find a comparable, yet lower priced product.

I'll let you know how I make out.

Cheers

oujakov · 28 July 2009, 18:26

My old Quicksilver air keel has been attached in only 2 places and was leaking slow air. I used Raft Sealant Kit "quick sealnt" that you inject through valve and then spread it inside by wobling, shaking and everything else possible to spread the liquid evenly inside the tube.
I don't believe it helped as the keel continued to leak a little bit, requiring repumping every 4hrs or so.

This is what I've used:
http://www.nrsweb.com/shop/product.a...89&deptid=1032

navaraman · 28 July 2009, 20:33

Hi,
Don't know if this will help at all, but a few years ago i bought an old sib type boat. They must have had a similar problem, as they had filled the air keel tube with expanding foam. This worked well, as long as you don't have to deflate/roll up the boat for transporting?.
Cheers,
Mark

1ThOFA87 · 28 July 2009, 23:46

Quote:

Originally Posted by navaraman

Hi,
Don't know if this will help at all, but a few years ago i bought an old sib type boat. They must have had a similar problem, as they had filled the air keel tube with expanding foam. This worked well, as long as you don't have to deflate/roll up the boat for transporting?.
Cheers,
Mark

Sounds like Navaroman is talking about that "Great Stuff" that you can use to plug or insulate pipes entering your home so that snakes don't get in. That's what I used it for. Sounds like it should work fine as long as you trailer the boat and don't have to dis assemble it.

S4Simon · 29 July 2009, 05:00

On the larger Zodiac craft with air keels only the rear section of the keel was adhered to the floor. The front is never glued. Smaller Zodiacs (3.4) and under are glued at both ends.

Keels can be repaired. You'll need to see where the leak is. If it's the stern end, then yes you should be able to open up and reseal. if the leak is along the seam, then you have problems. If leak is around the valve, then should be repairable.

chewy · 29 July 2009, 06:48

Can't you get a new one made by a tube manufacturer?

Ask one on here, its got to be cheaper than a $1000 to have one made and shipped out.

smokeeater341 · 31 July 2009, 14:44

Thanks to all for some very sound advice. I found a manufacturer who is shipping out a new one for a much better price. I love the "Zodiac" quality but it sure comes with a price when doing any repairs/replacement.

I'll post the results when I receive the new keel, along with a review of the company that is providing it.

Cheers

oujakov · 31 July 2009, 15:51

Quote:

Originally Posted by smokeeater341

Thanks to all for some very sound advice. I found a manufacturer who is shipping out a new one for a much better price. I love the "Zodiac" quality but it sure comes with a price when doing any repairs/replacement.

I'll post the results when I receive the new keel, along with a review of the company that is providing it.

Cheers

Who it is and how much you piad?

raymillard · 01 August 2009, 13:11

Don't bother to replace it. Go to Morrison's/ Asda, etc and buy 3 swim tubes @£3 each. Then gaffa tape them together to the thickness you need. You can use a breadknife to taper the front and back, and there you have it. It worked for me. They weigh next to nothing and will coil up to put in the boot.

smokeeater341 · 01 August 2009, 15:21

Quote:

Originally Posted by raymillard

Don't bother to replace it. Go to Morrison's/ Asda, etc and buy 3 swim tubes @£3 each. Then gaffa tape them together to the thickness you need. You can use a breadknife to taper the front and back, and there you have it. It worked for me. They weigh next to nothing and will coil up to put in the boot.

I love hearing about Morrisons and Asda's as my Aunt, who I visit yearly, lives in Ellesmere Port. I ordered one from a company named Aqua Marine Boats in Richmond B.C. for $100.00 shipped. It's a little bit longer than the original but it should still fit in the hull. If not, I will cut it down and re-glue one end. The only reason I'm reluctant to name the replacement company is that I don't want to send out the message that it's a good replacement until I receive it and put it to the test. Once I have undergone sea trials and if the product is as advertised I will give a full write up on my experience and whether this company/product is reputable enough to recommend. Thus far, communications with them have been great, specs and photos were provided accordingly and it looks like a worthy replacement....we'll see

The pool noodle idea is one I will keep for future reference as it sounds viable as well. I also thought about filling the old one with those styrofoam beads that fill bean bag chairs. I can buy them in my local craft store and although I won't be able to deflate/empty the keel, it will offer the flexibility that I need without the stiff rigidity of expanding foam. Has anyone done the expansion foam? What are your experiences? I fear that once filled and rigid, it would just break up into dust as soon as you put it under load. How would one fill it? In layers? Or all in one go, put the floor boards in and let it set in the needed position?

I appreciate all the positive feedback I have received and look forward to hearing and sharing other experiences with SIB's.

They're certainly a lot more suitable to my storage needs and on-water requirements, than my previous Bombard RIB (which I loved, did a lot of modifications to and got a lot of use out of)

Keep the ideas coming!

Cheers

oujakov · 01 August 2009, 15:36

100.00 is a good price, even for something like this of "so-so" quality. I'd take this for 100.00 any day over something tha is 1000.00 but "superb" It will be easier to repair in the long run, then something old, but original. Most of the companies make airdeck and keel of PVC, so it should not be a problem fixing in case of a puncture. I just saw that you're in Toronto as well, you can always PM me if you need a piece of PVC, as I have some at my house.

Just out of curiosity, can you post few pics of your motor (in the thread its OK), I want to see what kind it is, and may be sometime in the future we can get together and ride boats on the lake Ontario or Simcoe.

lightning · 01 August 2009, 15:37

I would imagine that if you filled the air keel with expanding foam/polystyrene beads then it would be difficult to fit the floor to the boat.
On our Zodiac 285s you have to fit the floorboards then get into the boat and stand on the last two to get them to fit in.
The air keel is inflated after this.
With a keel already fitted and "inflated" I'm not sure how you would do it.....it takes quite a bit of pressure to get the last two floor sections in.

smokeeater341 · 01 August 2009, 15:46

Quote:

Originally Posted by lightning

With a keel already fitted and "inflated" I'm not sure how you would do it.....it takes quite a bit of pressure to get the last two floor sections in.

That's my concern!

Quote:

Originally Posted by oujakov

Just out of curiosity, can you post few pics of your motor (in the thread its OK), I want to see what kind it is, and may be sometime in the future we can get together and ride boats on the lake Ontario or Simcoe.

Sounds good!

I'll post up some pics when I get back in later today. The motor is a simple 2 thumper, single carbed Johnson but the compression is solid and it runs well.

Cheers

smokeeater341 · 15 August 2009, 17:04

Latest follow up:

I installed the new air keel which came in as promised on time. Communications with Aquamarine were excellent and customer service was second to none.

The keel I ordered was 11" longer the OEM but I knew that upon purchase. Being anxious to see if the rest of the vessel was up to par, I filled 'er up to leak test it immediately. The first issue I ran into was the HR valve started to leak around the seat of the valve where it is fastened through the PVC of the keel. I used the supplied air fitting (My tube valves are the old style Zodiac ones that you rotate to fill each tube individually) to try and rotate the entire valve tighter until I found a spot that it seated reasonably well and held air. I'm not sure if there is supposed to be and "O" ring between the valve and the PVC (as there is none). What are the prescribed ways of tightening an HR valve if both ends of the keel are sealed and you can't access the inner ring?

It finally seemed to be holding air, so I folded over the excess amount, duct taped it in place (placing the folded end under the floor rather than against the hull) and re-installed the flooring. The valve was centred properly in the floor opening and the keel was sitting well in the hull. I proceeded to fill it up again and it seemed to be holding air sufficiently. On sea trials, the keel held up quite well considering the fold. There was no noticable shifting between the hull and floor and it was only after going through some rougher waters that the keel started to loose air. The SIB cut through the water really well and got up on plane quickly.

All in all I am impressed with the replacement keel although I now have to remove it again, figure out how to tighten the HR valve properly so that it holds air at all times and cut and re-glue the stern end of it so that it fits without having to fold it.

Questions that I have other than the valve are: Can I glue a PVC backed "D" ring onto a hypalon tube? Is it just a matter of using the right cement? Is MEK the prep cleaner of choice for hypalon and further to that, will it adversely affect the bond with a PVC "D" ring?

The last question is for raymillard. If I use the "pool noodle" method as a back up keel, would you suggest trying to fit it into the old keel? By that I mean, should I split the old keel open, fill it with the shaped pool noodles and then reseal the keel in order to maintain shape and protection?

All suggestions are greatly appreciated. I will post pics of the SIB as well as the replacement keel later today.

Thanks to all.