Engine choice for 4.2m Zodiac MKII

IvarNelson · 20 April 2014, 21:34

Whats your opinion?

I just purchased an unused zodiac MKII 4.2m SIB, which I am going to use for hunting birds in the archipelago and to bring on spearfishing trips to Norway. I still havent bought an engine for it but I want a standard tiller outboard.

The way I figure my engine needs/requirements are as follows:
1. The SIB will be deflated and packed for transport and engine mounted/demounted so engine weight and "handleability" plays an important role.
2. The SIB needs to get up on the plane with four people aboard in calm waters so that getting around to the different sites doesnt take too long.

It would be interesting to hear your opinions regarding engine size and make/model. So far I have been looking at yamahas 2stroke autolube models from 1990 and forwards. Any thought on these? Im thinking 30 hp but my neighbour who has had a few RIBs and SIBs tells me the rubber bottom has more drag and will require more power than an RIB, which is why he recommends that I get a 40 hp.

Thank you for your time.

Landlockedpirate · 20 April 2014, 22:05

Ive had a couple of futura's, a 3.8 fastroller and a 4.2 Sport. They are lightweight boats and plane easily. I used a 15 and a 25 with the 3.8, both worked well and in fact the 25hp was overpowered if it was lightly loaded.

The 4.2 Sport had a 2 stroke 50hp Yamaha and it was seriously quick, pulling a mono skier with ease from a deep water start.

I think your biggest issue will be portablility, a 25hp 2 stroke weighs about 45kg, it can be handled with difficulty by 1 person. A 30HP is usually 3 cylinder and significantly heavier but about the same weight as a 40hp. I think a 25hp will do the job, mine will plane a 4m HonWave with 4 big adults on board. If you are leaning towards the 30hp, you might as well get a 40jp because it will be virtually the same weight.

IvarNelson · 20 April 2014, 22:15

Good point!

Probably a good idea to stay with 2 cylinders then...
Any specific brand or model to look for, or to look out for!?

Landlockedpirate · 20 April 2014, 22:29

Just my personal opinion, but I love pre oil injection 2 cylinder Yamaha's, either the 20 or 25hp versions (The Mariners of the same era were identical).

The slightly newer Mercury/Mariner 25hp are also good, but a bit heavier.

headdamage · 21 April 2014, 04:33

I use both a Evinrude 15hp 2 stroke and a Johnson 30hp 2 stroke with my mkII. The 15 is nice for light loads when I don't want to hump the 30hp around. For much more than two people with little gear the 30hp is required, it is at the limit of what I can handle as a removable motor for beach launching.

Peter_C · 21 April 2014, 06:15

I have a 40HP, 2 stroke, 2 cylinder, Evinrude, mounted to a 4.2m Futura Sport GT. It lives on a trailer. There is NO WAY I would dismount the motor every time. I use a cherry picker to pick it up when I do need to remove it. You need to be reasonable about what you can easily lift, as a motor is fairly awkward to handle.

You are probably going to want the largest heavy duty transom wheel setup you can get to help get it in and out of the water. It is not a boat that a couple of guys can just pick up and throw in the water.

An electric air pump will make blowing the boat up far more enjoyable too.

spartacus · 21 April 2014, 07:38

Used to have a Yamaha 25D (2-stroke) on a Zodiac MKIIC (3.8m) which was perfect. If you're heading out yourself, I'd suggest a bag of sand secured up front as ballast. 25hp is as big as I'd go to lift. Also had a Yamaha 40V (2-stroke). Beautiful no-nonsense engine, but not easy to man-handle on your own.

Mantaclause · 21 April 2014, 08:11

Hi
I use a 30hp 2 cyl 2 stroke premix yamaha (30gmh I think the engine code is ) on my lodestar 380 air floor . I pack the boat away after use and transport it in a mazda bongo as I don't have the space to store it fully inflated ,and I find I can move it in and out of the bongo ok by myself ( I am fairly fit but certainly not the strongest guy around) .there is a technique to learn and I use a modified sack barrow at home and I use my launch wheels to get the boat as close to the back of the car as possible . I really like the engine it has good power and has been totally reliable and being a premix 2 stroke there is no oil to spill when it is laid on its side.

IvarNelson · 21 April 2014, 18:38

Thank you all very much for your valuable inputs!
I now think a 25hp 2cyl 2stroke will have to do.

About transomwheels and electrical pumps, any info on what brand/model to look for? A good dealer in europe?

Locozodiac · 21 April 2014, 21:53

If portability it's a must go for a 30 HP engine, are same size and weight of their younger 25 HP brother. Will benefit having that extra 5 HP if boating with 4 mates. Check 2 strokes Tohatsu 25 HP which could be converted to a 30 HP for candy cost.

If sib's tubes and keel are correctly inflated to at least 3.0 PSI while resting on water, lower fabric drag will pass near unoticeable. Just pump it up baby, pump it up....

Happy Boating

Shafe · 06 August 2014, 15:55

Has anyone experienced an MK2 Futura HD with 20hp 4 stroke?

How fast could you get with one person and spearfishing gear?

How fast could you get with two people and spearfishing gear?

If you have only experienced a 25hp, perhaps you can speculate as to what it would be like, relatively speaking...

Thanks!

IvarNelson · 06 August 2014, 19:12

I dont know about he MKII futura as I have a MKIIC classic (3.8m). But it sure flies with three persons on board with a 25 hp tohatsu 2 stroke.
Difficult to contol if I am going alone. I need to work out some counterweights to balance the boat. I think 20hp would be fine for 2 persons on a 4.2m boat.

Shafe · 08 August 2014, 11:46

This is what a local dealer said:

A 20hp is still within spec for this boat. 2 guys and gear the boat will still get on plane and scoot at 20mph +. I don't see any issues w/ it being underpowered - even in strong wind or current the motor will still have plenty of juice to get you moving. I have clients who water ski their kids w/ a 20hp motor and if you are somewhat athletic - even an adult can get out of the water on skis or a wakeboard. So again, although it is not "max" power - the minimum recommended will still perform and do what you need it to do. Moreover going large will just be too heavy for you and will not allow for ease of use. All in all, the 20hp will be the way to go and should still have plenty of power to scoot the boat

shaun2020 · 08 August 2014, 15:26

Very economical on fuel :-)

Wild_Bill · 09 August 2014, 15:09

Quote:

Originally Posted by Shafe

Has anyone experienced an MK2 Futura HD with 20hp 4 stroke?

How fast could you get with one person and spearfishing gear?

How fast could you get with two people and spearfishing gear?

I've got the shorter version, the Zodiac Futura Mk IIC with aluminum floor, and a 20hp 4-stroke Honda outboard.

With just me (and a ton of junk) on board, it gets up on the plane no problem and goes 24 mph. This is an exhilarating and somewhat scary speed. It is punishing on the back as the waves really hammer the hull.

With me and my wife, I'm sure that it will do over 20mph.

Of course, a bigger boat would be somewhat slower with this same outboard.

Keep in mind that I normally carry about 200 lbs of stuff (electric trolling motor, battery, heavy steel legs/wheels I had fabricated, misc safety gear).

I like my Honda outboard because it weighs only 104 lbs and I can manhandle it by myself. Anything larger would have to stay on the boat or require assistance to remove.

HDAV · 09 August 2014, 22:25

25hp 2 stroke tiller is going to be 50kg ish YAMAHA Two Stroke Outboards : YAMAHA 25NMHOS Two Stroke Outboard a 20HP manual start 4 stroke is about the same F20 // F15 2014 Features & techspecs - Outboard Engines - Yamaha Motor UK

If your hunting the fuel economy and quietness of the 4 stroke may be worth the lower power and higher costs perhaps add an electric trolling motor for sneeking up on the prey

MinnKota Electric Engines : Endura Max 50 36"SHAFT

Shafe · 10 August 2014, 13:19

Thanks for the details Wild Bill. I'm feeling good about the power and portability of the 20 hp 4 stroke now.

HDAV, the 2 stroke would be nice but they can't be sold here in the US any more due to its pollutants.

HDAV · 11 August 2014, 13:58

Quote:

Originally Posted by Shafe

Thanks for the details Wild Bill. I'm feeling good about the power and portability of the 20 hp 4 stroke now.

HDAV, the 2 stroke would be nice but they can't be sold here in the US any more due to its pollutants.

Not "new" anyway? Strong market for good used 2 strokes where they are allowed

Peter_C · 11 August 2014, 19:02

Quote:

Originally Posted by HDAV

Not "new" anyway? Strong market for good used 2 strokes where they are allowed

Which could be fewer and fewer places in the USA. There are a couple of lakes in California that have already banned them, and sure to be more in the future.

HDAV · 11 August 2014, 20:47

Quote:

Originally Posted by Peter_C

Which could be fewer and fewer places in the USA. There are a couple of lakes in California that have already banned them, and sure to be more in the future.

True, what do they do about stand up jet-ski's? Just ban them ?