Tiiny is Cavitating while turning!

[Zooter]

Hey fella's

Need sum advice on cutting tinny down as my motor is cavitating when i turn corners, like really bad :(

I spoke to a few ppl and was told that i can get the tinny cut down by a aluminium cutter, which i havnt looked into with prices but kinda sounds like it will cost more than what the tinny is worth.lol

Ive checked the that the cav plate is pretty much in line with the bottom of the hull , which from what i have read should be ok ??? but obviously isnt :P

Any thoughts or ideas would be muchly appreciated fella's

Cheers! :)

[Chimo]

Can you take a few pics of prop, and motor from side to show cave plate and bottom of boat?

Also what size motor and what size prop?

Condition of prop will be seen in pic.

Cheers
Chimo

[Lancair]

Try lowering the trim peg a notch or two.

With my 40 Etec trimmed for best speed I cant turn much at all without it cavitating, but if I trim down I can turn so hard it will nearly throw passengers out of the boat if they're not hanging on tight.

[Zooter]

Try lowering the trim peg a notch or two.

With my 40 Etec trimmed for best speed I cant turn much at all without it cavitating, but if I trim down I can turn so hard it will nearly throw passengers out of the boat if they're not hanging on tight.

She is trimmed as far down as i can go, but i have tried going up a notch but could just get on the plane and it would Cavitate in a straight line,

Yer and it aint real safe with the passenger thing, Im trying to get it sorted for a bit of fun with our new tube that i got my young fella for xmas,

but until i get this sorted and it passes a quite a few test runs the Tube will stay dry :)

chim, will get sum picts posted up later 2 day m8 , thanks :)

Btw, it is a 3.3M synper, 1999 15HP jonno short shaft

[Chimo]

Waiting for pics.

I didn't think it was possible to abreviate chimo but there ya go!

Cheers
Chimo

[Hornet Rider]

Waiting for pics.

I didn't think it was possible to abreviate chimo but there ya go!

Cheers
Chimo


Hi Chim, lol ::) welcome to Ausfish!

Hey Zoot, are you experiencing cavitation or ventilation issues? see attached link...sounds like your prop is venting is anger, ie ventilation issues.

http://www.boatinglife.com/article_content.jsp?ID=10937

cheers, HR

[Zooter]

Nice Find M8:)

I would be leaning towards Ventilation then,

If this is so, then would dropping the motor another inch down resolve this problem??

Not willing to fork out a few hundred if im going to have the same problem afterwards.lol

Only have 1 pict, my net is capped and takes bloody forever to upload. soz

http://img396.imageshack.us/img396/1650/dscf2944va7.jpg (http://imageshack.us)

[Hornet Rider]

Zooter, that poor old prop looks like it was used by the Spartans at Thermopolie, got a few pieces missing. Chimo & FNQ are good sources on these issues, I'm still learning engine height tricks, but the last thing I'd be doing is cutting your transom away. Bin that idea until things like motor leg length, effect of that foil, how you operate the boat in turns, prop matching etc are expored. Stand-by for 20 questions from others who will pony up to help you.

cheers, HR

[Zooter]

LOL ,

what pieces are missing??

I have no idea, ive had it for a year, its going on 10 years old,

Well its had issues doing the same thing without the foil on, she sits up a bit better with the foil on with a load, would a permatrim be better option than the chepy foil i have on it???

I had the motor on my old hull and didnt he any hassles at all, this hull is a bit shorter but heavier,

Just got back from an arvo fish on the kalang river, just cant do tight turns which doesnt really happen while your fishing anyway, but even backing off and coming into land with say a 70 ish degree turn it will do the same thing!

[Chimo]

Zoots

The photo you took indicates the prop, (the top of one blade is all we can see) has sustained damage and has lost some metal. To put in abreviated terms for you; it (at least one blade) looks to be "stuffed".

All blades needs to be "entire" and not bent and before you waste anymore time either get a prop sevice to fix or replace the prop and then see how the boat runs.

Chimo

[Reef_fisher]

Prop service should not cost very much, do the cheap things first, it sounds like you have done most or all of the no cost things. But man that prop looks very tired.

[pedrodepacus]

looking at the photo the keel extrusion which they have used needs to be cut back about 350mm as you will get dirty water coming off it. you should be able to take to them to have a look i think they are in toormina now

[skipalong]

mate try raising the motor 15mm and replace the damaged prop and i think you will be set

cheers justin

[Zooter]

Cheers fella's :)

Going to go with the new prop first, Then see how it goes, then Height Adjustment, Got me wondering why my local Mech didnt pick up on the prop first?

anyway...

Appreciate all of your time, Will keep ya's posted ! :)

[Zooter]

OK,

Took it to snyper at toormina, didnt even know they were there. lol

Wasnt the Prop, even though it looks like it been in 3 world wars :P

The motor leg was sitting to far out due to the back board being rooted,

Old M8 had to put chocks up the top to get motor to sit under better ,
raise the motor 1inch and Grind the keel down a bit.

Havnt taken it for a run yet but Old M8ty set it fly's and handles unreal now with no cavitation!

So while ive been waiting for them to fix that ive bought another boat an real one this time.lol

Picked up a 2005 4.1 poly with a 50 zuki 4 stroke for 12k,
LOL, Funny thing he wants my boat now for a car topper,

Things u do in a few weeks. :)

Thanks all for your help, Im sure i will posting up for thoughts on Mods for my new Rig :)