Repower of Haines 635L with Mercury 150HP ProXS 4Stroke

[zmk1962]

2 hours ago, flatheadluke said:

Thank you Zoran for a fantastic post. I learnt a lot from it. Torque is something I never really considered, particularly even torque.

i love it when someone looks beyond branding and relies on primary research and data to find the best value product that meets requirements. Your post highlights how much power buyers have these days.

Out of interest did you assess reliability and lifespan as a requirement? I have heard anecdotally other motors (chiefly the Yamaha) have an advantage in this area. Or is that marketing fluff?

Thanks Luke. 
Re reliability. Well those that have followed my FR posts may remember that I look after my gear and I had the Merc 200 for 21years with only 1 failure at the 18yr mark. So I personally have confidence with the Black brand. On the other hand I inherited a Yam 225 And ran it for 4 years and it developed a crack in the exhaust manifold - was told it was a common occurrence with that motor. As Noel said above you have to look at the specifics of the motor you are considering and I’d add look after it !

So specific to the Merc 150HP - it was launched in 2012 with no major flaws being reported so I gather the bugs are ironed out and the base design is proven.  The ProXS is a tweak. Comes with 6yr warranty. There is a lifetime warranty on the valve train. The gear case is oversized (JonD commented on this in one of his posts). Single cam design and in general has some 20% less moving parts than the other brands 4st design. It’s a simple 4cyl 4 stroke designed for DIY servicing. Annual service or at 100hrs. 
Anecdotal comments on other boating sites have owners reporting trouble free 600hrs+... one outlier at 10,000hrs(let’s treat that as marketing)

cheers Zoran 

[noelm]

The exhaust in the Yamaha model mentioned is one of those "features" I meant, lots of brands have faults, some real, some just hear say, just a couple I can think of, Yamaha 225 exhaust, 150hp balancer, Suzuki pre 2008 90/115/140 engine holder, 140 oil cooler, 175 butterfly screws coming out, Mercury's Optimax compressor failure, broken bolt in the alternator, e-tec injectors and EMM cooling, lots of things are easily "googled" and you just need to sift through the dirt to find the truth, most of these faults I have seen, repaired or helped someone with.

[kingfishbig]

On 7/2/2020 at 6:35 AM, noelm said:

I have said many times (and got roasted for it) that the old more torque with a 2 stroke business is dead and gone, modern 4 strokes have a much smoother torque "band" and this is especially evident when "cruising" the throttle can be more or less just set and the boat will maintain a very constant speed, this is great on long trips home from the shelf, older 2 strokes would die off on the back of a swell, needing throttle, they would speed up, hit their power band and take off, requiring backing off again, after a couple of hours, it gets very tiring. Great report, I like to see "real world" owners stuff, rather than rehashing internet myth and magazine paid advertising telling us how fabulous something is.

The new Mercury 4 strokes have good torque because they have a large displacement. No doubt this was done to compensate for the well documented deficit of 4 strokes in this respect (due to them having less power strokes per cycle). So you can't assume that other 4 strokes an the market will perform as well.  

PS: I haven't experienced those sort of problems with my carby two strokes - just abundant torque and power through the commonly used rev ranges. Anyway it's hardly a fair comparison ie the latest 4 stroke (with a large displacement) vs an old tech 4 stroke which you cant buy anymore.  

[Scienceman]

Great outcome Zoran. My Merc 60CT is being fitted as I write this. I'll update my post when I have taken it out and give feedback. I did manage to locate torque curves comparing the Merc 60CT with Yamaha F70 and as you found, the Merc curve is VERY flat. Going from 70 2st to 60 4st will cost me ~5km/hr off the top but like you, that doesn't worry me. 

[wrxhoon1]

9 hours ago, noelm said:

Most engine "stuff" is internet hype and old wives tales, there is no motor brand that traditionally lasts longer than the others, most makers have produced a certain model that has an undesirable "feature" but, in the main they are all good. When buying a certain HP, you need to research that model, not just general info, but, specific to that HP you're interested in, certain brands are better than the others for different boats. Lots simply fight for their favourite brand without looking at what a motor is going to be used for, some models are very heavy in certain HP, some have more cylinders than others, different gear cases, different controls, all sorts of stuff needs to be looked at.

I totally agree with that statement, another thing I found over many years of offshore boating , American built outboard engines are more resistant to corrosion than Jap built engines, both OMC and Brunswick. It must be the alloy the use in the casting .

Jeffb,

You can't compare a 2 stroke engine ( of any brand) to a 4 stroke for noise.

4 strokers are very quiet at idle speed , almost silent , on a boat like Zorans you will not know it's running if you are not looking at the tacho, just like a modern car. They idle very smooth unlike 2 strokers . Of course at high RPM they are noisy but again much much quieter than 2 st

GoingFishing,

Your comment about Jeffb is a bit harsh  and in my opinion unwarranted. We are here to learn from each other, not have a go on others because they may not know as much as you do.

 

[zmk1962]

7 hours ago, Scienceman said:

Great outcome Zoran. My Merc 60CT is being fitted as I write this. I'll update my post when I have taken it out and give feedback. I did manage to locate torque curves comparing the Merc 60CT with Yamaha F70 and as you found, the Merc curve is VERY flat. Going from 70 2st to 60 4st will cost me ~5km/hr off the top but like you, that doesn't worry me. 

Great stuff... hope your repower is as successful as mine. All the best. 
cheers Zoran 

[GoingFishing]

18 hours ago, Scienceman said:

Great outcome Zoran. My Merc 60CT is being fitted as I write this. I'll update my post when I have taken it out and give feedback. I did manage to locate torque curves comparing the Merc 60CT with Yamaha F70 and as you found, the Merc curve is VERY flat. Going from 70 2st to 60 4st will cost me ~5km/hr off the top but like you, that doesn't worry me. 

Congrata scienceman! Love to hear how it goes.

Sorry did you mean the Yammie torque curve was flat?

[zmk1962]

Hey Raiders,

Just an update regarding fuel economy. Yesterday I had the chance to go top up the fuel tank. It took 39.3L for the 64km Syd Harbour trip. That validates the instant VesselView readings I had reported above.

Calculated averages shows 0.614L/km or 1.628km/L  vs 1.3L/km or 0.74km/L on the old 200HP.  

Better than 100% efficiency improvement.... and as the motor runs in I should be able to squeeze out a bit more.

I am absolutely stoked.

Cheers Zoran

[antonywardle]

I went and had a look first hand. Its a big motor, It was trimmed down and a little of the ground but it was still taller than me.  Zoran's beard looks more magnificent in real life than in his photos, and he serves a very good beer! Thanks for the catch up!.

[zmk1962]

It was great to catch up Antony. We’ll have to do an offshore raid soon. 
cheers Z

[Fab1]

Love your work mate.Enjoy the new donk and trusty boat for many more years. 

[zmk1962]

Thanks so much Fab. Hope you’re doing well and staying out of mischief!

cheers Z

[zmk1962]

@jeffb5.8, back to your question of is the motor quieter .... I took the opportunity to cut out of the videos from the last fishing trip, some clips of the motor at different revs.  This was filmed with a GoPro 5 mounted under the alloy hardtop ... it has a more natural sound reproduction than the iPhones I used previously.  The net is at idle and trolling it's hard to hear the motor running over the noise of the ocean, at 3500-4500 (50kmh) noticeably quieter than the 200HP and easy to hold a conversation, when you get to the 5000rpm (60kmh) its loud and at WOT 70kmh it howls.... 

Cheers Zoran

[jeffb5.8]

15 hours ago, zmk1962 said:

The net is at idle and trolling it's hard to hear the motor running over the noise of the ocean, at 3500-4500 (50kmh) noticeably quieter than the 200HP and easy to hold a conversation, when you get to the 5000rpm (60kmh) its loud and at WOT 70kmh it howls.... 

Thanks mate

That’s the sort of information I was after as it’s a common question (Noise of Outboard) On my boat to the point I often contemplate changing to a 4 stroke.

But never thought about noise when on other people’s boats before I bought mine, for the most part its not a problem but is another thought when I upgrade or repower.

Edited July 27, 2020 by jeffb5.8