New motor required 150 V 175

[Streaker]

Hi
seeking some input from the experienced ones. Looks as though we need to replace the outboard on the Scam : - 6.5 metre plate boat Masters Marine design, weighs in on the water at about 1.5 tonne.
The onwer is looking at replacing the current motor with a 150 suzzi and I have suggested that a 175 be considered.
We will need to consider the cost difference between these 2 motors, the running cost litres per hours 5.5 V 5.8 at 4500 RPM.
My thoughts are: - a 175 would require less RPM to travel at the same speed and the extra power would be available when required.
Any and all responses will be appreciated.
Wayne

[Vitamin Sea]

Hi

What is the max the boat is rated to? I would always go max hp if given the choice and have the $$$

Cheers

[Streaker]

I understand that the manufacturer has indicated 175 hp, but as the boat was built 12 years ago there is no compliance plate fitted.
Wayne

[doublexl]

The 175 has variable valve timing and will be better on fuel.

[cormorant]

What is the current motor, 2 stroke , 4 stroke year , weight , brand and it's performance? Is thw owner happy with that performance- doe she travel cruise or wring it's neck? Ha sthat motor lasted 12 years and what hours?

Why not rebuild the current motor?

[BigE]

New 150 merc could be worth a look. big cube lazy motor.

[fisho8]

Price up the 150 Merc to the 175 zuk either should push that boat along quite nicely. I am running a 175 opti on the back of my Clearwater 2100 walkaround it get's along at 4000rpm doing 30mph with no hassles at all that extra 25hp makes quite a differance.:)

[Greg P]

Wayne I have the DF150 on the 6m Fisher and more than happy with it still after 550 hrs. It has been faultless but If I did repower it would be with a DF175 or even a 200. I steered away from the VVT back in 07 but probably should have pulled the trigger. Still the DF150 is good for 37.7 knots and will cruise all day 20-21 knots @ 3900/4000 for 1nm per litre offshore. Even better with the tide.

I don't believe the 175 would be better on fuel on my boat, if anything it would maybe use more with the increase in torque curve in low to mid rpm but would probably be quicker out of the blocks but not sure if I the difference would be huge. The VVT is just adjusting the vale timing/curves and other than that they are identical but not sure if the ECM is mapped different. At the end of the day it needs to hit a certain rpm with a certain pitch prop they just go about getting there different. If you got a good deal on a DF150 then I wouldn't walk away from it.

The AMM will be a well built boat so don't spare the ponies.

[Streaker]

Thanks for your input on this. the owner is looking at the 175, not much change out of $21000.
Wayne

[Dan5]

Just throw a spanner in the works............have you had a look at the 225yamaha?.......a mate just upgraded from a 150yammy to a 225 on his 609 Stabi........it cost him a few hundred to have the hull re-rated but by all accounts has made a significant difference to his speed and economy compared to the 150.


Dan

[John_R]

The Merc 150 is 165hp and the Suzuki 175 is 172 - 7hp difference, while the Merc is about 3 grand cheaper and 10 kgs lighter. The Suzuki is 2.8L while the Merc is 3L - both 4 cyl.

If the AMM was ok with a 150, I have an Opti 150 for sale - so I can upgrade to the Merc 150 4 stroke on my Noble 6.2.

[Smithy]

Dan, is that from the F150 to the new 4.2 litre 225?

Hard call. I was in the same predicement three or so years ago. At the end of the day the Yammie deal was the best for me through Brisbane Yamaha. They also threw in the electronic gauges with fuel flow etc. Suzuki didn't sharpen the pencil at the right time and Honda weren't in the equation price wise other than offering me full 5 year warranty on a commercial vessel when everyone else was 1 year. The 150 Merc wasn't in the equation at that time. It is worthy of consideration. Same for the F150 Yammie. It was a good motor and at 2.6 litres capacity I never ran out of horsepower on Wide Bay Bar etc. when I really wanted some power.

Like all these discussions, at the end of the day it will come down to your deal and what dealer you are most comfortable with.

[ranga7]

Just imported a 175 from the states and got plenty of change from $21000. $6000 in change once fitted.
Thanks for your input on this. the owner is looking at the 175, not much change out of $21000.
Wayne

[Dan5]

Dan, is that from the F150 to the new 4.2 litre 225?

Hard call. I was in the same predicement three or so years ago. At the end of the day the Yammie deal was the best for me through Brisbane Yamaha. They also threw in the electronic gauges with fuel flow etc. Suzuki didn't sharpen the pencil at the right time and Honda weren't in the equation price wise other than offering me full 5 year warranty on a commercial vessel when everyone else was 1 year. The 150 Merc wasn't in the equation at that time. It is worthy of consideration. Same for the F150 Yammie. It was a good motor and at 2.6 litres capacity I never ran out of horsepower on Wide Bay Bar etc. when I really wanted some power.

Like all these discussions, at the end of the day it will come down to your deal and what dealer you are most comfortable with.

I think so mate,it was fitted about 3 months ago so if the current engine is 4.2ltr then that would be it..........apparently it was lighter than the 200Yammy?..........The boat is heavily modified with over 750ltrs of fuel and 150ltrs of water,hard canopy at the rear built in cupboards etc etc......the little 150 did'nt cut it any more hence the HP upgrade.

Dan

[cormorant]

The Merc 150 is 165hp and the Suzuki 175 is 172 - 7hp difference, while the Merc is about 3 grand cheaper and 10 kgs lighter. The Suzuki is 2.8L while the Merc is 3L - both 4 cyl.

If the AMM was ok with a 150, I have an Opti 150 for sale - so I can upgrade to the Merc 150 4 stroke on my Noble 6.2.


Those numbers are on premium fuel in controlled conditions so in real life on the back of your boat I would be interested. Those numbers come off the labels on the transom brackets or dealer advertising?

I'll say this till I'm red in the face. peak HP is a bullcrap number unless you are racing in a straight line WOT. You need to have a good look at the torque curve on motors and at what revs/ fuel ecconomy they may good cruising power. A good prop and setup will make the same diff at 10hp in that size motor

The above is why some motors seem so tractable and so easy to drive on a boat. Not that they produce the best peak HP but because they have the right torque at the right revs with the right prop to keep the boat moving. Some motors in each catagory have this sweet spot. Others have their reputation as thier wide torque band mans they are suitable fro a wide range of boats of different set ups and weights and can make a average boat a pleasure as a package.


So at 3500 - 4500 rpm what hp are the existing and proposed motors making.

Bring on the dyno tests of run in motors I say and load the dyno with typical boat weight and prop profile so you can see how all the fancy electronics work on a motor .

[boatboy50]

John R,

Can you please point us all to the facts of where this is documented?

I see this sort of claim all the time, and am yet to see living proof of it as fact.

Darren

[John_R]

Calling me a liar Darren? You are a Suzuki dealer I am guessing?

I have been researching these motors for an upgrade for my boat. The numbers come from various engine tests on Boatpoint and other sources.

http://features.boats.com/boat-content/2011/09/new-mercury-150-fourstroke-outboard-debuts/

http://www.boatpoint.com.au/engine-reviews/2009/suzuki/suzuki-df175-14756

The boatpoint test above compares the Suzuki 175 with the Opti 150 (which is claimed 150.1hp) on the same Victory hull and the Opti performance and fuel economy is comparable. Why would I upgrade to a Suzuki for no gain over the Opti I have now?

I agree with Cormorant that peak HP does not necessarily imply better performance, but it does give some indication. In this case VVT increases high rev HP for the Suzuki, so it's possible that the Merc is a better mid-range performer.

I think the capacity and its resultant torque may be a better indicator also.

I have no vested interests in Mercury or Suzuki, but am impressed with the new Merc. That's all.

[The Woo]

I for one wish outboard manufacturers would make their power/torque graphs much more easily accessible than they are. It's nice to have a sticker on the cowling stating the HP within 10% @ the prop..... but graphs, and more specifically, torque figures, really do the talking.

If we were to be limited to just HP figures in the diesel inboard market, I'm sure Yanmar would sell more of their 4.2 litre sixes, because they're small and easy to fit.... but nobody would know that the torque figure in only about 2/3 of the 5.9 Cummins. Similar horsepower though! And we'd have a whole bunch of boats that wouldn't get out of the hole and onto plane.

If I were in this market for this range outboard, I'd be taking a REAL close look at the new 4 banger from Mercury. Especially if you're looking at keeping it long term.

[Mister]

Always look at the lowest HP for any similar capacity engine. Less stressed engine models will always be the best investment.

[Dicko]

I for one wish outboard manufacturers would make their power/torque graphs much more easily accessible than they are. It's nice to have a sticker on the cowling stating the HP within 10% @ the prop..... but graphs, and more specifically, torque figures, really do the talking.

If we were to be limited to just HP figures in the diesel inboard market, I'm sure Yanmar would sell more of their 4.2 litre sixes, because they're small and easy to fit.... but nobody would know that the torque figure in only about 2/3 of the 5.9 Cummins. Similar horsepower though! And we'd have a whole bunch of boats that wouldn't get out of the hole and onto plane.

If I were in this market for this range outboard, I'd be taking a REAL close look at the new 4 banger from Mercury. Especially if you're looking at keeping it long term.

So true.

Go buy an engine for any other application and you can compare the facts via torque figures etc, but outboards are damn near non existant.

Tohatsu have them available, but that's a little hollow when no one else supplies them to compare against.

The only other one shown around the place is a marketing poster from etec showing a torque graph better than a yammy, but no figures or data on the graph so it's nothing but sales hype.

[cormorant]

Always look at the lowest HP for any similar capacity engine. Less stressed engine models will always be the best investment.

In the days where all the motors used the same materials , approx bores size and technology that theory worked as the lazy motor lasted longer. These days there is so many variables in materials and design I don't think the arguement is as valid in regards to performance as VVT or electronics can get same performance more effeciently out of smaller CC. . Harder to compare apples with apples these days. It however stands that a simple older style motor of proven design should be Ok but what happens is some bloke in the office decides that to compete with the newer motors they need to trim some weight so lighten up some metal here and there so old relaible becomes more stressed. Problem is the manufacturers are constantly changing designs and the metals things are made out of and with new casting technology can do so much more quickly and cheaply than previously so different generaions of the same motor can gradually lose the very quality you bought the original version for. A lazy torquey motor. You just have to look at the ever relaible casting and bottom end of the johnsons that remain pretty much unchanged but the heads, pistons, fuel injection and exhausts have all changed. Same CC but very different motors from previous models, same hp but different tractability and a lot was just done to meet emmissions / fuel ecconomy.

The great thing with diesels is they are purpose designed as a pretty much constant load engine and rated for a number of hours at that load. They give the curves so peopel can use the right motor for the load required. Simple mechanical controls for that performance band and use worked. Run them outside that criteria and their lifespan changes significantly. Comes down to correct set up and choice in the end for the purpose and to meet pollution rules it is all electronic these days.

Everything is a compromise and with electronic engine management systems it is amazing what some motors can achieve.

[boatboy50]

Hey Mate,

I'm not here to have a slinging match. Life is too short for name calling. I simply asked to be pointed to facts. A forum is here to share information, which is what we both are doing.

See this link to Mercury's own website which states a 150hp Max on that engine.

http://www.mercurymarine.com/engines/outboards/fourstrokes/150/?model=0

I couln't find that engine on the boatpoint site to compare apples to apples, using the same data source.

My reading of your initial link to me doesn't say the engine produces that hp at the prop, but i'm not a mechanic either so it's all jargon to me.

Interestingly, your boatpoint links also show the Suzuki 140 to put out 138hp.

http://www.boatpoint.com.au/engine-reviews/2005/suzuki/suzuki-df140-8328

A pet hate of mine is to see on this forum and others it claimed as only putting out 128hp which I believe to be false.

Anyway, engines aren't my thing, and i'm no mechanic, so I won't defend them as vigourously as you appear to want to, so i'll move onto something else.

Darren




Calling me a liar Darren? You are a Suzuki dealer I am guessing?

I have been researching these motors for an upgrade for my boat. The numbers come from various engine tests on Boatpoint and other sources.

http://features.boats.com/boat-content/2011/09/new-mercury-150-fourstroke-outboard-debuts/

http://www.boatpoint.com.au/engine-reviews/2009/suzuki/suzuki-df175-14756

The boatpoint test above compares the Suzuki 175 with the Opti 150 (which is claimed 150.1hp) on the same Victory hull and the Opti performance and fuel economy is comparable. Why would I upgrade to a Suzuki for no gain over the Opti I have now?

I agree with Cormorant that peak HP does not necessarily imply better performance, but it does give some indication. In this case VVT increases high rev HP for the Suzuki, so it's possible that the Merc is a better mid-range performer.

I think the capacity and its resultant torque may be a better indicator also.

I have no vested interests in Mercury or Suzuki, but am impressed with the new Merc. That's all.

[John_R]

Darren,

You could have said that in a way that didn't make out you thought I was deliberately spreading bunkum. We can only go on the info that is available, and that isn't much. Andrew Norton is pretty reliable so if he states 138hp for the 140, then it's probably correct.

Several other sources have noted 164.9hp for the Merc 150, so I reckon that's probably right too. Merc's formal specs just list the nominal HP.

Way things are going, I will not find out - no calls for the Opti in several weeks. Might just give up and keep it.

[Swanie1975]

im another one for max hp on the hull especially if you compare the weight of the suzi 150 v 175

interesting that the japanese motors seem to be packed full of high tech while the new merc has taken the more back to basics approach - be great to see how the motors stand the test of time. with auto engines it amazes me how the germans seem to be able to squeeze out huge hp/kw per litre compared to the others. do the likes of BMW or Mercedes have any marine products?

John R, i found the articles interesting to read and i noted that the performance of the merc 150 was with a 16p prop - funnily enough the holeshot was great as was the midrange. it should be with that low a pitch;D i wonder what it would rev out to ?

cheers ryan:)

[John_R]

The Suzuki 150 and 175 are basically the same motor with the significant difference being VVT on the 175. Weights are within 5kg. Nice motors, but expensive and not offering me any advantage, other than less noise. They were released in 2005/2006, and have remained pretty much unchanged since then, so kinda old and boring too.

Here is a comparison of 150 Four strokes and DFI you guys may find of interest:

http://www.boatpoint.com.au/engine-reviews/2006/mercury/150hp-four-strokes-and-dfi-two-strokes-comparo-8370

Unfortunately this is too old to include the new Merc 150 fourstroke.

I currently run a 15" Mirage Plus on the Opti 150 which gets it to 5300 (WOT Rev range 5000-5600). Holeshot and general performance/economy are very good. Prop selection depends on the hull etc, but a prop that allows the motor to get to the mid/upper part of the WOT rev range is essential, so that the motor is not overloaded.