Help! Zodiac Futura Mk2 - Yamaha 50H Prop Pitch???

ZodiacFuturaMk2 · 15 August 2007, 12:41

I have just purchased a new 2007 Zodiac Futura MK2 HD and installed a 1999 Yamaha 50HML two stroke long shaft outboard with manual start, gas assist manual tilt (just under 70kg I think)

This outboard is fitted with a 10 3/8 x 13" prop.

At full throttle this very lightweight boat (4.1m long & 100kg) does 30mph. In the 1998 Zodiac brochure it stated the Futura Sport (white and yellow) which was a much heavier boat did 60mph with the same 50H!!!

This new outfit that should be superb isnt even as good as my old 96' Futura with a 30Hp yammy.

So three questions:

1) What pitch prop for max speed???

2) What pitch prop for skiing / wakeboarding???

3) What height should the outboard be mounted?? At the moment the Anti Cav plate is in line with the bottom of the transom / hull.

Many thanks

Gareth

p.s. I have no idea what revs the engine is running as it is very basic and has no speedo / rev counter!

Nos4r2 · 15 August 2007, 12:46

What pitch prop do you have at the moment?

Jelly · 15 August 2007, 13:38

Hi Gareth
I used to have one of the HD versions of this boat and I also had the cavitation plate level with the bottom of the hull.
The problem we found was that it accelerated fine while the boat was lifting on the hull, once the boat stated to lift onto the futura hulls (the extra inflatable tubes like runners on the underside of the main tubes), we got ventilation.
Once this last lift happened the prop was lifted out of the water causing the Ventilation. If you can I would lower the engine so that the top of the ventilation (cavitation) plate is level with the bottom of the Futura tubes. This will allow you to get all the power of the engine in to the water and not to Ventilate.
I would also look at the steering ram installation the zap cats have because hand steering a 50Hp on a light boat will kill your arm quickly !
I miss my old zodiac for the fun side but not for the arm ache from holding that yam 50 !
good luck
James
Just looked at your picture and can see your steering is not hand held so the zap cat comment is no use.

ZodiacFuturaMk2 · 15 August 2007, 14:47

The Prop Pitch is 10 3/8 x 13" at the moment

Also the new redesigned futura has much larger main tubes, speed tubes and the keel is much lower and acts like a third speed tube so I guess the anti cav problem isnt so bad now!

Cheers for your replies

Gareth

ZodiacFuturaMk2 · 16 August 2007, 14:39

Anyone - know what prop to put on this engine to get higher speed?

fast fred · 17 August 2007, 10:29

Stainless 15-16 " of pitch, cupped, thinkin that hull should have a 15" shaft
not a 20"

jack it up one hole at a time she what she dose, watch your water psi

ZodiacFuturaMk2 · 17 August 2007, 10:37

Many thanks fast fred

The new futura Mk2 takes a long shaft for some reason - bigger tubes I guess.

What do you mean by psi? - Its now mounted at max height and still doesnt cavitate.

Cheers

G

fast fred · 17 August 2007, 10:57

looks to deep from hear. some basic rules for getin it to go fast on the water.

1) rule number one is, to go fast on the water you Must get the hull Out of the water.
your hull dose this on it's own cuzz it's air intrapment style.
2) drag, got to get rid of it.
the prop, from 12o'clock back around to 12o'clock, or one turn of the prop,
from 4:30 to 6o'clock is all the power to push the boat, no mater what.
from 6 o'clock back around to 4:30 is All drag, to get rid of it you serface the prop.
thare is a fine line between cav', runnin it out of water bein to high for that style pick up.

13" of pitch is too short on that hull.

fast fred · 17 August 2007, 10:58

jack plate

ZodiacFuturaMk2 · 17 August 2007, 18:08

Right ive taken some more photos of where the engine is mounted in relation to the bottom of the transom, keel and speed tubes. Any comments welcome. I just took the boat out - it was rough conditions but it didnt cavitate even in sharp turns. I just it could do in calm conditions if I got it right up onto the speed tubes, Im not sure.

As said before the prop I have at the moment is a Yamaha Aluminium 13 pitch I think I will try same prop but a 10 x 15 Lip Cup - sound better??

Many thanks

Gareth

fast fred · 19 August 2007, 13:02

if it was mine, i'd bolt a 1/2", 13mm, alu plate on thare, about 2-3", 48-75mm,?,
higher than the transom, so the top two bolt holes were above the transom,
see if i gots a shot.

fast fred · 19 August 2007, 13:17

hears a plate

this is a shot of what your tryin to make it work like

this bein the far end of ware your tryin to go

Jelly · 20 August 2007, 08:24

Hi Gareth
before you go making anything just try dropping it two bolt holes, should take to you a few mins and seeing if that makes any difference, its a no cost test.
Mine was set up like yours for height and it needed dropping a bit.
Easy way to adjust it is lift the front of the trailer up put a block of wood under the engine leg to support it, remove top bolts and slightly loosen bottom ones. then slowly lower the front of the trailer until the bolt holes you want to use line up then a dob of sealant and bolts back in an tightened
Rgds
James

ZodiacFuturaMk2 · 20 August 2007, 13:37

Thanks for all your responses

I am going to order a Aluminium Yamaha 10x15 G (Lip cup) prop and see if that makes it a bit quicker!

Yamaha also do a 16 and 17 pitch prop but these arent lip cup - whats the advantage of the lip cup??

Going to order the 15 this afternoon unless people think I need to go larger on this very light setup??

Also Ive been advised to drop the engine so the plate is 1" lower than the keel.

Cheers

G

Davidgriffiths · 20 August 2007, 21:36

Gareth

I am no expert but I would not drop the engine, it already looks much lower than where we are running our 25HP on the Mark IIc and we get 34mph.

With regards the Futura Sport they were faster, as the speed tubes were much bigger and hence lifted the boat further out of the water reducing drag. The fact that we were running a short shaft 50HP would also help. As for the magic 50mph got there a few times with a light load and the wind behind us.

David

ZodiacFuturaMk2 · 20 August 2007, 22:51

Thanks for your response David.

I guess your 2c is a short shaft and the older shape with pointed rockets? Be great to see any pics you may have showing where your anti cav plate is in relation to your keel on 2c OR futura sport!

In 2003 they changed to the new shape futura with huge main tubes and hull profile and speed tubes the same as the old futura sport!! They did this tube size increase to allow for the new heavier four stroke outboards and therefore the boats take a long shaft and zodiac recommend that it is mounted so the anti cav plate is level with the keel!

Im trying to get futura sport (now discontinued) performance out of my new large tubed even lighter Mk2. Hence the pull start / manual tilt / 2 stroke light Yamaha 50H!!

I would really love to know what pitch prop you had to do 50mph?? Zodiac claimed the sport would do 60mph with the right prop! Im changing from 13 pitch to 15 to try and get better than 30mph and get top revs down as boat is so light!!

Any advice / pics / suggestions most welcome.

Kind regards
Gareth

Davidgriffiths · 21 August 2007, 09:44

Gareth

Down with the boat this weekend, so will try and take some pictures. Will check at home if I have any of the futura sport.

David

Realruler · 24 August 2007, 10:27

Looking through my brochure boxes, I have come across a Zodiac 2003 one. Here is what it says:

"100% PURE ADRENALINE

The Futura Sport is guaranteed to make your adrenaline flow. The speed, up to 60mph*, is simply incredible and piloting requires all yuor concentration. The sensations are like those of an off-shore powerboat racer. Despite this brute performance, Futura Sport remains very comfortable with the Futura hull absorbing bumps and giving smooth and predictable handling. Spacious and well equipped, this racer also makes a good family boat and ensures you get the maximum out of even modest outboards.

*Fastest speed for the class acheived by a professional team using a 50hp motor and a special propeller. NOT TO BE ATTEMPTED BY NON-PROFESSIONALS"

Overall length:4.20m
Weight: 101kg

Ask dealer for prop pitch

In the same brochure it states that the Mk 2 Futura S does 37mph max. Will try to get pics of brochure online!

Hope this helps! - dunno how.

ZodiacFuturaMk2 · 24 August 2007, 10:38

......what is this magical 'special' propeller!!??

Someone must know about this Zodiac fastest speed in class title and what setup they were using! ;o)

As in theory my setup should be just as light with the same engine! It must have been a highly tuned 50hp - and a jocky on the jocky console!

Cheers for the post

Gareth

fast fred · 24 August 2007, 11:59

15,16" of pitch, hears a 50, makin 60+hp

up, up is ware the speed is.