Repowering advice

[butters]

Gday all,
I'm going to repower my 660 trailcraft. Looking at either a 150 or 175 horsepower 4 stroke outboard. I have narrowed the choice down to Honda, Yamaha or Suzuki. I'm interested to hear people's first hand experiences with any of these outboards, especially in the way of fuel economy, service costs and any problems encountered etc. Please let me know what boat you have it on and any fuel economy figures you might have.
Cheers and thanks in advance!
Nick.

[Noelm]

Honda... Best warranty at the moment, and a good motor too, mind you, they are all good!

[tenzing]

175 suzi 4 stroke on seafarer victory (hull 1100 kg)
Cruises at 0.6 - 0.7 litre per km .WOT 0.9- 1.0 litre per km
Trolls ( 6kn) at 0.4 litres per km on the flat.
Have been very happy with it.
150hp is same motor so I would go the 175 option.
Prop will make a difference so do as many trials as you need .

Cheers
Brendan

[butters]

Good info thanks very much Brendan. Is that 1100kg bare hull only?
How are the servicing costs?
Cheers Nick

[tenzing]

Yep bare hull
id have to check last service cost to be sure

[PROS]

What is the max hp rated for your hull Nick?

6.4mt+ boat with 150hp, you are looking at poor performance and over fuel usage there.

Nothing like having 200 ponies under your control acting like second set of kahunas...

Max The Turk

[butters]

Gday Max,
Maximum horsepower is 225. Minimum 115.
Cheers

[scottar]

Short of funding being an issue, I would get the most HP for weight in what ever platform you end up choosing (also check your spec for maximum transom weight). Suzuki 150 - 200 4 cylinder all weigh about the same, Same with Yamaha. The Honda is heavier from 175 up but same deal from 175 - 225. Yamaha have some performance reports from a similar sized Seajay on their website if you are after round numbers. Take into account warranties and your level of trust in your service establishment - a big thing for this sort of investment. Look at prop swap programs just in case you aren't happy with the original option.

[butters]

Thanks Scottar. I have been most impressed with Honda so far. Best price by a mile

[butters]

Best customer service as far as I have experienced and best warranty (7 years). Suzuki have been the next best to deal with. Suzuki and Yamaha around the same price for 150 but 175 much more expensive in Yamaha. Only hang up with the 175 Honda is that it's substantially heavier than the others as its a 3.4L V6. Also unsure in the effect this may have on fuel consumption? For what's it's worth, both Hondas have lean burn, but not sure exactly how much difference that would make.
Cheers!

[Spaniard_King]

Lean Burn feedback ensures the engine is running at optimum efficiency at all times. It basically ensures you are not waisting fuel!

[Spaniard_King]

Butters, your PM box needs clearing

[butters]

Spaniard King, all cleared.

[PROS]

As long as your transom is rated to the weight of the outboard, it has pretty much no effect to performance of the boat.

I had a Yamaha 135hp 2stroke carby outboard on my 6.4m glass boat before 2006 model it was.
Although it was a gutsy engine, had to push hard on the throttle to cruise.
Results was just under a lt of fuel per km, very heavy usage for that boat.

Replaced with 200hp Yamaha hpdi 2stroke which is significantly heavier than previous engine, my fuel consumption now is almost halved to 1.8km per lt of fuel.
The difference is not just because hpdi is more efficient in fuel economy but 200hp is working a lot less stressed.
Cruising 50km/h just under 3000rpm, I can almost plain just above idle.
Not to mention some crazy top speed.

Engine weight has hardly any effect to economy as I can load the boat with 4 people and still achieve similar economy if it was a solo trip.
In fact heavier boat rides better in my case.

150hp will be on the smaller side for that boat regardless lean burn or not.

Max

[scottar]

Unfortunately there is no easy answer to your question Butters. Pros has given an example for which it has been a vast improvement. There are other cases where exactly the opposite is true, and some where the extra weight simply means a few modifications are required to make the boat do what you want it to do. The extra weight will most likely not be noticed if you are a calm weather boater. Where it is most likely to rear it's head is in rough conditions where the extra transom weight may (in my case definitely) translate into extra boat speed required to maintain a fuel efficient plane. This extra boat speed unfortunately then translates into a harsher ride. In my case I fixed it with trim tabs and a Permatrim to generate transom lift so I could plane slower. As a general rule though with 4 strokes, powering with a higher horsepower will produce a greater benefit in economy provided it doesn't ruin the balance and dynamics of the hull. A fourstroke's economy benefits are typically realised to a greater extent if you can keep your cruising rpm below 4000. Once you start to work them harder they still like a drink. To give you some comparison figures, I have the same outfit as Tenzing but with a 200HO Etec. In flat water, my typical economy at cruise is about 0.8l to the km. At WOT though I have the same economy at 1l to the km. There is also another member floating around here that runs a Victory with the 225 Honda, who had to ring his insurance company as it is a few kilo's over the rated transom weight, who achieves better economy again - but once again, hull modification was required to see the best from the boat in rough conditions.

http://www.ausfish.com.au/vforum/showthread.php/186408-REPOWERING-the-VICTORY

[butters]

Found out some info on hull weight today- 900kg. Bearing in mind it has had a 150 2 stroke on it before and performed just as well as the 225 Etec on it now, bar a little too end speed, maybe 10km/hr or so. 2 stroke however was a 2.5L V6 merc so maybe more torque than a 4 cyl 4 st?

[rtp1984]

Found out some info on hull weight today- 900kg. Bearing in mind it has had a 150 2 stroke on it before and performed just as well as the 225 Etec on it now, bar a little too end speed, maybe 10km/hr or so. 2 stroke however was a 2.5L V6 merc so maybe more torque than a 4 cyl 4 st?
You do spend a lot of time in that extra 10km/h range.

[koastal]

Curious as to why you have elimanted Mercury. Bad experience in the past ?

Paul Burt has just re-powered his new boat with a pair of 150 Mercury's.
(maybe a deal that isnt avaliable to the general public )

General consensus o/s is they are 160hp+ motor and quite light at 206 kg. In conjunction with Enertia propellors they would imo be a good match for your 660

[Dogtoooth]

I think you will be wanting more Hp if you go 150-175hp, they will do the job. Four strokes are doey when they are pushing big hulls. Honda, Suzuki, Yamaha are all in par these days, check the weight. Go close to your max HP, getting a 225 Hp you could easterly sit on 3500RPM with the right prop when cruising, saving on fuel, noise, wear. A outboard that has done 100 hours is equivalent to a car doing 13000 km, so a oil change only, every 50 hours won't hurt if you decide to keep it and run it into the ground.

[butters]

111094111095111096
Thanks for the input fellas. Here a a few interesting bits of info from a boat test with a very similar boat to mine. It was a 150 Honda and my boat is approx. 150kg (give or take) lighter according to specs. This has got me thinking.... Also is there any truth to the rumour that the 150 Honda is actually 160+ hp at the prop? Cheers

[butters]

That's cause the lowest cruise speed with the 225 is around 45km/hr if I want any sort of economy. Also waterline length makes a big difference :P

[fishtragic]

Hi Butters,
As stated above you will be better off with the extra horsepower. You'll appreciate it carrying heavier loads and consequent fuel savings. Also when you need to get out of a hole in dodgy conditions or bar work you don't want sluggish performance from less HP and I feel that's what you'll have with the HP you're considering. As for brands, they're all pretty good these days. You asked for opinions so my 2 cents worth is I wouldn't have anything other than Yamaha. I've run Yammies commercially for many years and can't fault them for fuel efficiency, reliability or service. I've had Mercury, Mariner, Evinrude and have many acquaintances and friends with all brands. Two friends have just had major failure with relatively young Hondas due to internal corrosion (internal anodes were the issues) but that's not to say Hondas aren't worth considering, just do more research. Personally, my last runabout had twin Yammies with over 4000hrs when I sold it and they still performed like new. Currently I have a 6m Seafarer with 200HPDI Yamaha and its also been faultless, just over 1000hrs. I've got no affiliation with Yamaha I've just had a really good run with them. Good luck.

[butters]

Thanks guys. Keep the feedback coming. I'm not sure if the photos I posted actually worked? My only fear with the bigger horsepower is that my economical cruising speed might be too fast? Currently with the 225 on the back, my most economical cruising speed is around the 45km/hr mark which is too fast for most days offshore. To achieve the desired speed(about 30-35 km/hr) the motor seems to about too much on lower revs and results if poor fuel economy of around 0.7km per litre.

[butters]

Koastal, as for Mercury. The reason I have taken them out of the equation is that their four strokes only range up to 150hp. After that you have to have a verado, and I'm just not convinced on having a supercharger on a marine engine, that's all.

[Darren Mc]

You should be able to alter your cruising speeds to a degree by experimenting with props.

[scottar]

The fuel economy curve of the 4 stroke is totally different to the Etec. It will also be a totally different animal to drive with a lot less tendency to want to "run away" once the vessel starts to plane. The exact reasons you are talking of with your Etec is why I added the trim tabs and foil to my hull. IMO the minimum clean plane speed of the hull is more influenced by transom weight than anything else so unless you remove a heap of weight off the transom or look at other ways of getting the stern lift, you may find that the minimum speed where the hull runs the most efficiently doesn't change that much. You will use less fuel due to the change in the fuel burn curve but may well find it is better again with extra stern lift and a whole lot more drivable at low speed.

[snatchy]

Thanks guys. Keep the feedback coming. I'm not sure if the photos I posted actually worked? My only fear with the bigger horsepower is that my economical cruising speed might be too fast? Currently with the 225 on the back, my most economical cruising speed is around the 45km/hr mark which is too fast for most days offshore. To achieve the desired speed(about 30-35 km/hr) the motor seems to about too much on lower revs and results if poor fuel economy of around 0.7km per litre.

As Darren said, I can't help but think that if you experimented with props that you should be able to bring some more economy to your lower cruise speeds. I'm not sure how much you have tried that with your current setup? Is the cruise speed economy issue the main reason you are looking to change outboards?
Experimenting with different props to find the characteristics you want should be true for your new choice of power too.

I wouldn't underpower the rig. It will be disappointing. A more powerful engine running at lower revs will not be as loud and should be quite efficient.
By the way...those photos are not visible to me

[butters]

http://www.boatsales.com.au/reviews/2009/ED-ITM-14493/MakoCraft-650-Island-Cab

http://www.hondampe.com.au/docs/marine/fuel-consumption-reports/Fuel%20Consumption%20Data%20Sheet%20-%20Mako%20Craft%20650%20Island%20Cab%20-%20BF150A4XD.pdf

These are the links to the boat test for a 150 Honda on a very similar boat to mine. About 150kg heavier than my hull weight.

[The Black Unicorn]

So a 6.6m boat that can't sit comfortably at 45km/h offshore?????? Maybe just go with the less HP option then.

[The Silver Unicorn]

So a 6.6m boat that can't sit comfortably at 45km/h offshore?????? Maybe just go with the less HP option then.

Sounds like a riptide

[rtp1984]

So a 6.6m boat that can't sit comfortably at 45km/h offshore?????? Maybe just go with the less HP option then.
Just out of interest, what mono 6m boat will be comfortable on all offshore conditions?