first time out with new rig

[slate1234]

I finally got out this morning, cloudy but nice and flat, I have a coupple of questions, I'm useing a 3.2m sunsport v airfloor along with 9.8hp tohatsu, I seem to be getting a lot of cavitation from the prop sounds like it's spinning and I also have a large air bubble towards the rear of the air floor any help would be great, I can get to 10mph before these two problems start
Thanks

[Landlockedpirate]

I would guess they are connected. Air floors, especially the V type need to be at exactly the correct pressure to stop them bending. The cavitation (Or more likely ventilation) is probably being caused by the less than smooth water flow under the hull.

Make sure you check the floor and tube pressure after its been in the water for 10-15 mins, then pump up as needed and it should sort out the problems.

[Peter Dobie]

In response to the bubble in the floor, I have found that it only happens on calm water as it builds up then starts to wave the floor gently even with the floor at top pressure. You might find in slightly chopped conidtions this might be less frequent due to the hull skipping across the rougher water and not building up the force on the hull. Thats my experience anyway with a 3.2 honwave 2007

[slate1234]

Thank you for the replys, regarding the floor I didn't check the floor once on the water I think I was to excited just getting out lol, I took some fishing takle and that didn't even get damp lol, I think the cav plate was a bit high as I got a lot of cavitation every time I turned, or opend the throttle so I have taken 25mm out of the transom useing a router along with some sikaflex it only took 20mins, I will try again in the morning weather permitting and let you know how it goes

[slate1234]

I tried again today with the same results I am pumping the tubes to 0.25 anf floor to 0.35 useing this gauge I use the inner red part, is this correct ?? the boat gets on the plane easey with two of us in but the bulge in the floor is causeing a lot of ventilation/ cavitation (prop seems to be in and out of the water)

[Peter Dobie]

On my honwave the pressures are 0.25 in tubes and 0.8 floor, so 0.35 seems very low to me, when I turn the boat over I can stand on the v without it collapsing and im 75 odd kilos! What does the manufacturer suggest pressure wise for yours or does it not mention any?

[slate1234]

Thanks Peter sounds like I'm under pressure, I can't seem to find any info on a 3.2m sunsport,

[Peter Dobie]

No problem, id say that yours is the same as honwave just different branding so get it to 0.8. If you hand or foot pump it, you can sure feel the pressure build towards the end so go steady if using a hand pump and go slow so you dont snap the pump shaft.
Good luck

[rik_elliott]

Or get a bravo pump - dial in the pressure and off you go

[Locozodiac]

Slate, it that 9.8 a short or long shaft Tohatsu ?

Happy Boating

[slate1234]

9.8hp short shaft,

[slate1234]

I rang a dealer today they told me that I. Could take the pressure to 0.5 for the floor

[manonthemoon]

Good to hear from a fellow Sun Sporter. The brand seems to get a bad rep on here but their identical to the Honwave and made in the same factory.

Anyway, just to confirm what Peter said. The Sun Sport manual states 0.25 for the tubes and 0.8 for the floor. Anything less in the floor and it compromises the ride and effects speed and handling. And also Landlocked's advice is worthy of note.

I've had my 3.2 for a couple of years now and it's been great fun however it's crucial that the floor is 0.8 when it's in the water. By that I mean if you pump up the floor to 0.8 and put it in the water, the cold water will of course lower the temperature of the air in the floor and so will lower the pressure. So a nice rigid floor on land can turn into a floppy thing in the water. My routine is pump it up to 0.8, put it in the water for a few minutes until the air in the floor stabilises i.e falls to the temperature of the water and then pump it up to 0.8 on the water.

This is of course a lot easier with an electrip pump and a small battery as the foot or hand pump is a bugger of a job on the water. A bravo pump and 12v battery is an essential investment if you're inflating and deflating on a regular basis.

I get 17 mph wot with a merc 6hp so I would imagine yours will fly with the 9.8.

Hopefully I've attached the relevant manual page.

Cheers
MOTM

[slate1234]

Thanks manonthemoon for that, do those pressuers apply to a deep V hull ?? or just to infltable keel and hard floor

[Locozodiac]

Unless you want to explode your keel go for it, keels works best between 3.0-3.5 psi. 3.0 is enough. Flat air decks and V deeep decks works between 0.8 to 12 psi.

You could inflate that V deep floor to 10 psi, once on water should stabilize to around 0.8. Nice thing to count with an electric 12 volt pump. Usually at afternoon if boating all day long, deck will be at a underinflated condition. Pump it up, pump it up.

Still find cracy to inflate a deep V keel with just 0.8 psi, probably that brand doesn't know what they selling and wants to be on the safe side regarding inflating to a lower pressure in case of a Kabum if going higher.!!!!

BTW, those hard inflatable decks are not plain baloons as in a inflatable bed, upper and lower fabric has thousands of crissed-crossed fibers glued between them, so stands hard working pressures.

Happy Boating

[manonthemoon]

Slate -this is for the deep v hull.
MOTM

[Landlockedpirate]

Originally Posted by Locozodiac

Unless you want to explode your keel go for it, keels works best between 3.0-3.5 psi. 3.0 is enough. Flat air decks and V deeep decks works between 0.8 to 12 psi.

You could inflate that V deep floor to 10 psi, once on water should stabilize to around 0.8. Nice thing to count with an electric 12 volt pump. Usually at afternoon if boating all day long, deck will be at a underinflated condition. Pump it up, pump it up.

Still find cracy to inflate a deep V keel with just 0.8 psi, probably that brand doesn't know what they selling and wants to be on the safe side regarding inflating to a lower pressure in case of a Kabum if going higher.!!!!

BTW, those hard inflatable decks are not plain baloons as in a inflatable bed, upper and lower fabric has thousands of crissed-crossed fibers glued between them, so stands hard working pressures.

Happy Boating

You are getting your units mixed up, the floor needs to be inflated to 0.8 Bar which is 11.6 Psi

I'm pretty sure EP Barrus know what they are doing

[slate1234]

Ok so I finally got again today, inflated the keel to 0.7 Bar and tubes to 0.3 Bar and I can say it was perfect I launched an hour before high tide and it was flatish enough to get 23mph WOT on my own, caught a nice cod while fishing and on my way in had a pod of dolphins following me, I got back to the van and my wife said there was a kayaker on the horizon, so back out two miles to check he was ok and all was good, he even gave me some markers for bass and cod
So Thank you all for your help from a very happy siber

[Locozodiac]

Originally Posted by Landlockedpirate

You are getting your units mixed up, the floor needs to be inflated to 0.8 Bar which is 11.6 Psi

Posters should specify wether Bar or PSI, some post just states plain mumbers, great difference betweeen them. 12-14 PSI is fine for most air decks.

Slate, seems you're overinflating tubes with 0.3 Bar, max just 0.25 Bar or 3.5 PSI, unless manufacturer stated. In plain summre will achieve an overinflation that could be harmfull to tube seams. 3.0 Bar is around 4.5 PSI.

Happy Boating

[Landlockedpirate]

Originally Posted by Locozodiac

3.0 Bar is around 4.5 PSI.

Happy Boating

You wont have many happy boating days if you think 3.0 Bar is 4.5 psi lol.

3.0 Bar is over 43 psi