Repower Help

[Greg001]

Hi All, I've got old 19c Haines Hunter about a 1970 model. My dilema is that the 200hp Mariner that's on it (while a great motor ) is getting a bit thirsty. At 5200 rpm I can cruise on 36 knts which suits me nicely in flat conditions. About 1.5 to 2 litres per NM weather dependant.
What I would like to do is repower with a 4 stroke but can anyone tell me if I can drop Hp? For example can I drop down to a 150 or 175 4stroke and still get similar performance or do I need to keep it at 200 hp?
Greg

[bigpat]

Don't have first hand experience, but I'm told the new 4 strokes can achieve 2-3 km/Ltr at cruise, so big diff in economy. Most older 4 bangers get around 1.5 km/Ltr at worst.

Regarding power, I'd say stay the same for a 4 stroke, maybe 175 for a 2 stroke.. The V19 is quite a deep vee boat with not much lift generated by the hull, as well as being a solid heavy construction.. They are rated to high power for a reason. My mate has V19 with a 200 as well, and he feels he wouldn't drop hp either.

A lower horsepower 4 stroke won't match the rpm/ speed that you have now. A 2 stroke makes more low end torque, and horsepower down some way from max rpm, which makes them a little more flexible. Don't discount the increase in transom weight either.

Look at any 4 stroke power curve, and max torque is normally 2/3-3/4 up the rev range, and horsepower is right a top of the rpm range, where you would rarely want to have a 4 stroke in interests of longevity and reliability.

Dunno, some will criticise this, but maybe look at the E-Tec or Optimax? Gives you 2 stroke torque, happy to sit at WOT ( no cams, valves going nuts, and less friction), if that's your thing, and good economy. After your current engine, noise from these won't be an issue I would think.

Just my opinion, but I've thought over the pros and cons of this for a while myself.

Pat

[Greg001]

Thanks for the response Pat, I was looking at E-tec but following the other thread not so sure now. I'll have to do some more asking around I think.
Thanks again,
Greg

[bigpat]

If resell value is an issue, then maybe listen to the others regarding E-tecs. If you planning on keeping her, who cares?

I have heard my fair share of horror stories about both E-tecs and Optimax's. I would think that if they were that bad, I would think they wouldn't sell any would they? As with any engine, you hear about the bad rather than good ones. I believe that you can always end up with a dud engine, no matter which you choose, just like any other mechanical device.....

From my experience on surfing different forums, ranking in terms of most problems/complaints on recent engines are:

DFI 2 stroke:
1. Yamaha HDPI (Yamaha have now discontinued them)
2. E-Tec
3. Optimax

I would say E-tecs are quieter, and opti's have stronger gearboxes. From what I hear torque is on par, and economy goes to the Opti. Optimax's are the cheapest to put on the boat a well. Each has their merits, personal choice in the end. I'd have either one to be honest.

As for 4 strokes, you don't hear many dramas overall. Heaps of Yamahas out there, so I take their greater number of complaints with a pinch of salt....

I believe Honda rules in terms of reputation and resale, then I'd say Suzuki. As I said Yammies have a solid rep as well. I believe 4 strokes are a tricky thing, as some claim better power to weight ratios, but by squeezing power from smaller displacement, you lose out on torque, it's a simple fact.

For example compare the DF 140( 2.0 ltr 185 kg) & DF150( 2.8 Ltr 220 kg). Besides 10 hp difference, there would a significant difference in torque, which to me is an important factor not often considered.

Same when comparing the 996cc Yamaha F70, compared to other heavier, bigger displacement engines. Some don't care about this, and that's fair enough too, their choice....

To be honest, when I bought my Cruise Craft, what steered towards this particular one was the fact that it had a HONDA, on it's bum. Make of that what you will.......
Cheers,

Pat
9546095461

[CT]

Don't discount the increase in transom weight either.

Dunno, some will criticise this, but maybe look at the E-Tec or Optimax?


I would take note of this advice. I have a 72 Cruise Craft and these old hulls were not designed for the extra weight of modern 4 strokes. There are numerous threads of new motors on old boats ending up too heavy in the bum.

From a happy Ficht ram owner, if your happy with an E-tec and it fits the bill, don't right it off just on hype.

Cheers
Craig

[Floating Rib]

lots of guys on here love there opti's, may be wrong but you might be able to run slightly lower hp than you have now with an efi 2 stroke but would think similar hp for a 4 stroke. Mate runs a 20ft hydrofield with a 150 Mariner efi(opti same thing) which i thought would be way underpowered but it actually does ok and economy is good. Interested to hear what the guru's say.

[no chicken tonight]

Horses for courses mate. I think 5200 rpm is beyond "cruise" rpm, and any fuel efficiency benifits a 4 stroke had would be out the window. If you want to keep your 36knot cruise speed, youd better stick with the opti or etec, as I dont think 4 strokes would be happy sitting over 5000 revs continuous. Just my opinion.

[bigpat]

Agree. I was advised early on that you want to hold 4 strokes above 4500rpm for extended periods of time if you can avoid it. Just logic that frictional losses increase as you rev engines higher, particularly with 4 strokes, due to the extra parts in the valvetrain.

Some do hold them flat, and have no problems. I myself am not interested in going everywhere flat out,typically sitting at a quiet and relaxed 4000 rpm.....

[thelump]

I'd love to see a 200HP 4 stroke get 2-3km/l. I am lucky to get 2km/l from my 115 4 stroke. A 60 or 70hp would probably get that but a 200 will be around 1.5KM/L. I have been on Honda900 new 625 Haines Hunter with a 175 Suzuki and it goes great. Plenty of power and gets around 1.7KM/L on average. I reckon that would be a good match for the 19c.

[hainsofast]

My mate is going through repowering his boat at the moment, he is going up from a 90 2 stroke to a yamaha 100 4 stroke. I couldn't believe the price of the etecs, they are nearly 50% more coin that the same size yammie 2 stroke. If you are looking at performance, mercury do have an extensive page full of tests on various hulls and motors, may give you an idea of what to expect. This link may help you.

http://www.mercurymarine.com/engines/engine-tests/outboards/

[Crocodile]

Hello Greg001 ,
Is your Haines one of the very old external chine models or is the newer shape.
Some points to consider;
Your preferred cruising speed is pretty fast, 36 knots is about 66kph.
Use Yamaha as example, I am not advocating Yamaha, all motors offer similar performance.
If you look at Yamaha performance charts and similar boats eg.
Streaker 525 + 150 4s
http://www.yamaha-motor.com.au/sites/yamaha-motor/files/Streaker_Tournament_585_F150.pdf
66 kph comes at 5500rpm, which may shorten engine life.
55 kph(about 30 knots) comes at about 4500 rpm, would that be fast enough for you?
To me the real decider is $$$$.
150hp Yamaha 4s is on special at $17689
http://www.##############.com.au/yamaha_outboards/f150aetl.html
For that you don't even get a propellor + about $750 fitup + any surprises.
200hp Yamaha 4s is on special at $21660
What would you get for the old Mariner, I will be generous and say $5000.
The changeover to 4s will cost about $12000 + fitting.
If your only reason to change is to save money on petrol, $12000 buys a lot of petrol!
You would have to do hundreds of hours per year to justify that expense.
You may also be over-capitalising on what is an old boat, so limited re-sale, even with the new motor.

Are there any other reasons why you want to change, eg. reliability?

[bigpat]

Good points, well said....

[Midnight]

My mate has a 200 Suzuki on a 213C, and it hit 51kts on the first sea trial. Empty boat.
Loaded with all the family boating gear it still does 46kts on the pins, and a 30kts+ cruise is easy work.

I do know of a 19C with a 150 Yamaha on it, and it hauls ass.
I can get some numbers for it if you like?

[hainsofast]

If your only reason to change is to save money on petrol, $12000 buys a lot of petrol!
You would have to do hundreds of hours per year to justify that expense.

This is a great point and one I regulary use when people say I should swap my 150HP yammie saltwater series for a four stroke.

[Greg001]

Ok wow thanks guys, Lots of info to chew over.
Wide open throttle it's revving at 6000rpm and cruise revs 4800 to 5200rpm with 17 pitch prop which is what my mechanic has said is right for my set up.
It is an 1983 carby model outboard with the oil injection removed, so I premix in the tank which doesn't bother me.
As far as reliability goes I can't fault it, I have had small issues with wiring but nothing I haven't been able to fix up enough to get home.
Yes she is a very early model with external chines and the large reverse chine. the fibreglass in the hull is about 6mm thick. I know this from when i replaced the transom and stringers. And yes I would be happy to drop to around 30 knts cruise. I have a mate with a 175 suzuki on a 19c haines and his cruise speed is down to around 23 knots thats why I didn't really want to drop too much in HP and asked the Question here.
While I say reliability is not an issue I suppose it is because my decky is my 14 year old son and when your a long way offshore that does play on my mind a bit.
$12000 can buy a lot of fuel and trips.
Once again thank you to all for the input and opinions.
argg my head hurts now information overload :)
Greg

[bigpat]

You love it Greg......

If you do decide to upgrade, go with your gut feeling. You don't want to second guess yourself later on......