Be carefull with the NANO hulls

[Cobra Jet Steering LLC]

I am on my 4th N A N O hull and so far every single one has developed leaks in the front possibly from beaching , although I have 2 nice anchors and I usually anchor my skies away from the shore I do bring them up close to the beach when add fuel.
I never let my tanks get to 1/2 since I just may want to go for a very long ride on a whim and I hate worrying about fuel. So I add fuel several times a day.
Last week I was riding my white 2014 FX HO cruiser with 300 hours on it.
I alternate them to keep the hours as close to even as possible. I was 5 miles from my launching point and I felt like I had weeds in the pump so I did my reverse move but nothing came out from under the ski like it usually does.
So I found a sand bar and felt up under the intake grate but nothing was stuck in there.
I decided to go slow since the hood was vibrating pretty badly at speed.
Then I noticed the water coming up over the hood and it dawned on me that I was taking on water. I know DOOH!
On these skies if the water gets high enough it gets into the dampener behind the engine and causes all sorts of vibration. I looked inside the ski and confirmed my suspicion.
I now had 5 miles to get back to my trailer, so I drove it back , in hind sight I should have pulled the 2 drain plugs and kept the ski going fast, this would allow the water to escape , I just did not think of that at the time, fortunately I managed to get back with no water ingestion, but it sure drained for a long time when I put it on the trailer.
I noticed the front of the hull had worn through in the curve of the bow " the usual place" .
So a word to the wise keep an eye on this and remember the ski will not sink even if you put it in the water all day with the plugs out so if you are taking on water you can pull the drain plugs and go fast to keep the volume of water low in the hull, mine was about half way up the engine but it never missed a lick. Also keep in mind that if you feel the hood vibrating violently at speed check for water in the hull "lots of it!"
I did thoroughly rinse everything and re apply white lithium grease to the engine and clamps and repaired the hull as I always do and I beef it up for better results.

 

[Ramblin Wreck]

Do you have pictures of the hull prefix?

 

[Cobra Jet Steering LLC]

no I sure don't sorry. it is basically 16 to 20 inches below the bottom of the bow eye where the hull curves upward

 

[Ramblin Wreck]

How bad was the hull. I bought a used 2015 ho recently and due to rain didn't lay on the ground to inspect the bottom of the hull. When I got home, after driving in rain for several hours, I washed it. When trying to get to the very bottom of the ski I noticed some decent scratches. I asked the dealer if they thought it was an issue and they didn't think it was an issue just a cosmetic one. Again, you can't see if bending over, you literally have to crawl under the ski. Based on what you just went through, should I be concerned at this point or do you agree that it is just cosmetic for now? I have put 12 hours on it since the purchase and haven't had an issue. Just wanted your opinion.

 

[Britboater]

Can you not fit a keel guard?

 

[robert843]

@Cobra Jet Steering LLC that stinks especially if you are not beaching all the time. I always beach my Kawasaki and the old Sea Doo and the only wear I have had was approaching a unfamiliar island and not realizing till to late the beach was all rocks. I jumped off just before it hit to try and stop it as I had already killed the engines but it still slid on a little causing a few scuffs. @Ramblin Wreck I'm no expert on Nano hulls Jeff would be able to answer that question better but for as few total hours as your skis has I would be shocked if that was from normal beaching. It appears more along the lines someone hit something or did the same thing I attempted and beached on rocks or something.

 

[Cobra Jet Steering LLC]

Just forward of your scratch the hull is very thin. It does have Styrofoam behind it, but that gets water passing through it and it gets inside the hull .
When it gives it is usually caused by an impact even a slight one, Once I banged into a big turtle . The hull was fractured but it did not leak as bad as the one the other day. I repair these hulls by removing the water from the foam using a specially designed fitting on a huge wet vacuum and sucking it out. Then I use a special fiberglass matt that is sewn to fiberglass cloth , no talcum powder is used in this material, I use a 4 to 1 epoxy with the coloring agent mixed in it. You can not use regular fiberglass resin or mat on these hulls so I've been told anyway.
What I like the most is after you grind the hull you can stand in the sun and you sparkle.

 

[Ramblin Wreck]

My scratch is about 25 inches below the eye. I kind of thought it was from getting on and off a floating dock as I've seen that before, but I really have no clue. I would be incredibly disappointed with Yamaha if this minor issue gave way to water. I just can't imagine their hulls being that weak.

@Cobra Jet Steering LLC Could you see the styrofoam or any fibers?

 

[Cobra Jet Steering LLC]

The composite fractured in lines parallel with the center beam of the hull and yes I could see the foam between the cracks it was sort of like fracturing bamboo long fractures and thin pieces between the cracks, you could push it in with one finger. I did not get all excited about it since I have had this issue with all my NANO hulls and I keep the repair materials in my shop, knowing it will happen, I just wanted to give a heads up to the vibration symptoms for the benefit of others who may have the same experience and the fact the removing the drain plug would have been a better way to travel that distance taking on water. Being that it was being forced in the front , fortunately the siphon helped keep the water from getting any higher.
Skies have a constant siphon attached to the pump to suck out water as you drive. The Styrofoam slowed down the water enough to keep it from blasting through the hull.

 

[Ramblin Wreck]

@Cobra Jet Steering LLC you sir are a lot more loyal then I would be. If this happens to me without my on negligence it will be my one and only Nano. Thank you for the info!

 

[Cobra Jet Steering LLC]

Naa I don't sweat the small stuff I look for reliability in the engines and pumps, I once owned a new Kawasaki supercharged ski, nothing beats that for the piece of shit award. I wouldn't take one now if it were given to me. The hull was strong but everything else was crap including the warranty.

 

[Cobra Jet Steering LLC]

Took it out today for 8 hours and beat the crap out of it as I usually do, burned 24 gallons of gas, checked the hull periodically just to be safe , no water inside, no water out of the drain plugs when I put it on the trailer so all is well once again.

 

[Julian]

I gather they don't have a hull warranty?

 

[Cobra Jet Steering LLC]

I would guess they do but it is faster and easier for me to do it myself, like I said I have had to deal with this on every one of my Yamaha hulls.

 

[Julian]

I would guess they do but it is faster and easier for me to do it myself, like I said I have had to deal with this on every one of my Yamaha hulls.

Yeah...that is one of those catch22 situations....the only way Yamaha will address the problem is if they get enough warranty complaints....but if it is faster to fix yourself....who wants to wait for the dealer to get to it...especially in the spring!

 

[Cobra Jet Steering LLC]

After 3 days of constant use the hull is just fine now, not a single issue but I did not expect any since I have done this 4 times on 4 different hulls .

 

[marco fiorenza]

I have a 2016 fzs, and I always beach it at my ramp, and have noticed some scrapes at the very bottom of the keel, the general area you are talking about. If I continue to use this ramp and beach it the way I do, do you think I will have the same problem as you are talking about? Or could I just fill the scrapes in with a repair compound?

 

[Big Shasta]

This question didn't get answered (or I missed it) wouldn't a keel guard protect from this?

 

[Beachbummer]

If it's caused by friction and not fracture, the keel guard ought to help greatly, as it should take on the wear. If it has to do with a fracture due to impact, it may still help some by dampening and distributing the force of the impact. Maybe Mr. Jeff at @Cobra Jet Steering LLC could put one on the other ski and see how long, if ever, if fails. Not sure who else has such a good set up for an A/B experiment, but that's the only way I know to find out for sure... Experiment Sample and Control Sample, observe.

 

[Cobra Jet Steering LLC]

Well EVERY single nano hull I have owned has failed and fairly soon like in the first year or so, I build up the area with special epoxy resin and special fiberglass mat with no talcum powder in it so it will work with the resin I also add the color, I cover it with wax paper and use a Bondo spreader to get all the air out and smooth it while it is wet, after it hardens I remove the wax paper.
I owned a body shop and a mechanical shop for many years so working with this is not all that difficult for me.
I believe the shield on a new hull may be a good idea but I have never tried one myself. The nano hull is the one thing that I personally do not like and I do beach the skies.
I do not see the hull wearing through with the epoxy resin and fiberglass on it however if it does I just redo it.
One of my skies failed so badly that it almost sank Fortunately Yamaha skies don't sink and no water was ingested in the engine either but when you feel the vibration dampener on the back of the engine causing the hood to rattle and vibrate real bad you probably have a hull full of water causing the issue.
If you push on the center of the hull right at the bottom of the leading curve and you see it flex or if you put the trailer with the nose down and you see a damp spot where water hi seeping back through the hull it is time to repair it and getting all the water out so you can fix it correctly well that is another trick I came up with that apparently works since this hull I first posted about is still doing just fine.