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From Yamaha to Mercury, think I will


Scienceman

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Well after 20 years of good service my Yamaha 70hp two stroke has finally gone terminal. Nothing wrong with the engine, just the hydraulic trim and tilt finally died to wear and tear (main cylinder scored, metal shavings internal etc). Cannot be repaired and cost to replace .......~$4,000! I looked at US and Japanese parts websites and still at least $4K. So time for a new donk. Was thinking a Yamaha 70 but my local Quinnie dealier is Mercury and he propositioned me with the 60CT. Specs look identical to the old 2 stroke Yammi except for the hp. Sure its going to be a little slower out of the hole but all 4 strokes will. EOFY sale, $10K fitted with gauges etc. Seems like a nice price. Will call the nearest Yamaha dealer on Monday to see what deals they have on offer for the F70 but I expect the Mercury will be a few thousand cheaper. My boat is a Quintrex Bayranger Caprice 475 and weighs 365kg so with engine, me and some gear, looking at ~600kg total. 

So if anybody is running a newish Mercury 60CT and has some comments, please let me know. 

Edited by Scienceman
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You should speak to @zmk1962 and get some advice. He is also repowering his boat and has done a tonne of research, he's repowering with a Merc too at this stage as the grey ghost doesn't cut the mustard on torque. 

Even more important if you want the value benefits of dropping 10hp

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I have just been involved in an old Evinrude 70 swap to a Yamaha 4 stroke 70 because of weight concerns, the new Yamaha wins in every department, still able to pull kids on tubes, way better fuel economy and about 2kph faster top speed, dropping down to 60 would be a backward step, and the Mercury 75 weighs a ton, that would be why the dealer is pushing the 60, but, it's your boat, and your money, you have to be happy.

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Thanks for the vote of confidence @GoingFishing but all my research has been focused on shifting from 2St to 4St technology in motors in the 150-200hp range, so I cannot directly comment on any of the make / models that have been discussed here, as they are engine block designs that I have no experience in or done any research on. But it sounds like @noelm has some practical experience in this class of motors.

However, what I can share is the generic information that has helped me narrow the field in my search. It is universally applicable to any outboard selection. 

There is a perception, largely built out of all of our auto industry experience that HP is king. But in the marine engineer community there is a saying that "HP sells boats/motors, but it's actually Torque that moves them".  When you dig into it, this makes a lot of sense.

Torque is the twisting force that a motor can deliver and all motors due to their design deliver different Torque output at different RPM - they have an optimum RPM range for max Torque (and hence max HP).

HP itself is calculated as follows HP = (Torque x RPM)/5252  ... so ask yourself, when we see all the HP numbers attributed to our outboards have we ever actually been told at what RPM that HP was generated? Is that RPM range useable to us? Have we ever actually been shown the Torque the motor produces at different RPM?  Rarely if ever. But we largely focus on that one HP rating number as the basis of our next 10-20yrs of investment. When in fact its the twisting force - the Torque at the Prop - that should be our main concern as boaties.

Here's why.

Most of our experience is with Automobiles. And In the Auto industry, yes HP is king, because we can bring the max Torque RPM down through gearing for effective use. eg and F1 racing car with a blown 1.5L engine produces 700HP at 10,000rpm.... but you can't drive the tyres at 10,000rpm so they have gears to bring that max Torque down to usable RPM, and then shift gears to keep the engine spinning at max torque RPM with each gear driving the wheels at a rate that can efficiently transfer the max Torque to usable motion.

No ask yourself how many gears does your outboard have?  ONE.

It's the one gear in the lower leg that takes the crank shaft HP ( a function of RPM and Torque) and reduces it to drive the prop shaft. The reduction is typically in the range of  1.75:1  to  2.08:1. For simplicity lets say this gear is 2:1 so if the motor has a Rev range idle to redline of 700-5800, the prop would be spinning 350 -2400rpm. 

And if we are spinning a 17p prop (with no slip) the boat would be travelling 350rpm 11.3mph (18.1km/h) to 2400rpm 38.6MPH (62.1kmh) in that rev range. Your boat speed is totally gated by that one gear and the prop pitch that you are running.... but at which RPM does that engine produce its rated HP? 

And does that engine produce enough Torque in the RPM range that you need for your boating - you can't change gears on your outboard to keep the engine at its max HP (Torque x RPM) while spinning the prop at the required RPM for the speed you need. 

So for an outboard motor it is absolutely crucial in which RPM range does the motor produce maximum Torque, because we have four critical phases in boating:

1. idle to plane (hole shot): motor 700-2500rpm: Most boats are well on the plane by the time a motor is at 2500rpm  .. prop at 1250rpm 17p prop 20.1mph (32.3km/h). (For instance my hull planes at 20km/h)

In boating we need a lot of torque in this 700-2500rpm range !!!  2Stroke delivered this for years because every 2nd cycle was a power stroke. Early 4St motors borrowed from the Auto industry (with Torque optimised for high RPM designed to use gears to generate low end RPM Torque) lagged low end Torque due to the outboard single gear design for many years - the max torque was too far up the RPM range to be useful in hole shot... so the industry norm was to install a bigger HP 4st than the 2St you are replacing to keep hole shot performance. Bigger HP usually derived from bigger capacity motors and hence more overall torque at the low end. We had to oversize the 4st to preserve the Torque required for hole shot -- and then that brought in the oversized motor weight consideration.

2. Plane to midrange (ride the wave): motor 2000-3000rpm. This is where offshore boaters need torque to keep the boat on a plane on sloppy broken seas, either to climb waves or control coming down the face. Motor 2000-3000rpm is 1000-1500rpm at the 17p prop ie effective speeds of 16.1mph(25.9km/h) to 24.2mph(38.8km/h). A typical boat can't do more than that speed in broken seas - your motor needs to deliver the torque you need in this RPM range to maintain control.

3. mid range: motor 3000-4000rpm: This is typically cruising speed. The boat is now on a plane and as fishing boaties we want max economy (efficiency) and optimum cruising speed (17p prop no slip, motor 3000rpm, prop 1500rpm  24.2mph (38.8km/h); motor 4000rpm prop 2000rpm 32.2mph (51.8km/h)). If we were towing skiers we'd want more torque in this range as well. 

4. top end: motor 4000-red line (typically 5800-6000 rpm) ... at these RPM ranges  with that 17p prop you are travelling at 60+ km/h ... may be of interest to the US lake fisherman, but how many times do conditions allow Aussie offshore boaties do these speeds? But interestingly thats the RPM range at which many outboard manufacturers rate their max HP!  In my case - completely irrelevant.

So putting all these thoughts together, and setting aside engine weights for the moment, a 60HP engine of the right design may actually produce the same or more usable Torque than another vendors 70HP engine in the RPM range that you do most of your boating. You may be sacrificing some top end performance but it would be the better choice for your most common boating experience. 

BUT sadly all this analysis requires you to get your hands on Torque to RPM data for the engines you want to compare. ???? 

In my case, I searched for months and found that it actually exists in the US boating community - it seems there is a very competitive spirit still in the US and the different manufacturers benchmark competitor outboards and actually publish HP and Torque curves at trade show and such. There are many forums where avid boaties photograph and share this type of data.

Here's an example of some 150HP comparisons: 

image.png.189464bc62b874418c1a80260b18aa52.png

In the above example, the 4St Merc improved the low end RPM torque over a 2st design by some 20-30% in the early planing RPM range, by specifically building a marine 4st engine. Torque is force x distance (lb.ft, Nm etc). They created more force by increasing the capacity of the engine cylinder (more volumetric fuel to explode) and increasing the distance from the crankshaft - a bigger lever - hence generated more low RPM torque for hole shot. This is still a 4St design where each cyl only generates power every 4th cycle - it burns fuel every 4th stroke and there's the 4st fuel economy. Put simply this motor throws more metal around further from the crankshaft.  This engine in several independent tests  (Perth, Melb, Bris) on different manufacturer 6m+ FG hulls consistently delivers 4sec hole shot performance - I don't think thats too shabby against any 2st expectation. All due to the focus on delivering maximum Torque in the low-mid range RPM.

The motor also seems to generate its max Torque in the 2500-3000rpm range - right where I want it for that plane-midrange RPM performance - for broken seas (remember motor RPM determines my hull speed due to the single gear - I need to go fast enough to plane, but can't go too fast due to the conditions but I need the torque at that RPM to keep my position on the wave.)

Anyway, hope this lengthy discussion is of some help. Perhaps do some googling for the engines you are considering Merc 60CT and Yam F70, and see if you can track down a torque/rpm curve for each. Or find test cases or users and get some data points: Hull weight on water, motor RPM, speed, prop specs. 

Remember "HP sells boats/motors, but it's Torque that actually moves them".

Cheers Zoran

PS1 - some other rules of thumb, obviously a higher pitch prop needs more torque to spin it, but moving 1p between propeller pitches has about a 6% variance in speed. I've done all my calcs here on a 17p and no slip. Typical acceptable slip is 10-15%, if its more than that you need to have your set up tuned (motor height - cavitation/ventilation, size of prop diameter and pitch etc). So consider these factors in setting your prop rpm pitch to speed expectation. I can share links for these calculators if anyone is interested.

PS2 -  this same vendor (BRP) that produced the chart above has compared, Suz, Yam and Merc and has produced Torque RPM curves that are floating out in google land. PM me if you want the links - again I have only focused on the 150HP range specifically. 

PS3 - and this is off OPs topic but helps with some of the decision logic on what is usable. The chart above clearly shows the 150hp eTec is a great engine - in this comparison it may lag Torque in the planing RPM phase but produces 20-30% more Torque in the mid-range RPM - if my boating included towing skiers this would have been a contender - prior to the recent BRP announcements. But in the same breath looking at the curves it's somewhat over engineered for my planned typical boating use. Just like a 200HP 4St may be oversized- I can't use the additional Torque to spin the prop any faster in that mid range due to hull speed/sea conditions. I'm sure this will generate debate which perhaps should be moved to a different topic so the OP original question is not polluted especially if the discussion is specific to my 150-200hp decision.

 

Edited by zmk1962
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6 hours ago, zmk1962 said:

Thanks for the vote of confidence @GoingFishing but all my research has been focused on shifting from 2St to 4St technology in motors in the 150-200hp range, so I cannot directly comment on any of the make / models that have been discussed here, as they are engine block designs that I have no experience in or done any research on. But it sounds like @noelm has some practical experience in this class of motors.

However, what I can share is the generic information that has helped me narrow the field in my search. It is universally applicable to any outboard selection. 

There is a perception, largely built out of all of our auto industry experience that HP is king. But in the marine engineer community there is a saying that "HP sells boats/motors, but it's actually Torque that moves them".  When you dig into it, this makes a lot of sense.

Torque is the twisting force that a motor can deliver and all motors due to their design deliver different Torque output at different RPM - they have an optimum RPM range for max Torque (and hence max HP).

HP itself is calculated as follows HP = (Torque x RPM)/5252  ... so ask yourself, when we see all the HP numbers attributed to our outboards have we ever actually been told at what RPM that HP was generated? Is that RPM range useable to us? Have we ever actually been shown the Torque the motor produces at different RPM?  Rarely if ever. But we largely focus on that one HP rating number as the basis of our next 10-20yrs of investment. When in fact its the twisting force - the Torque at the Prop - that should be our main concern as boaties.

Here's why.

Most of our experience is with Automobiles. And In the Auto industry, yes HP is king, because we can bring the max Torque RPM down through gearing for effective use. eg and F1 racing car with a blown 1.5L engine produces 700HP at 10,000rpm.... but you can't drive the tyres at 10,000rpm so they have gears to bring that max Torque down to usable RPM, and then shift gears to keep the engine spinning at max torque RPM with each gear driving the wheels at a rate that can efficiently transfer the max Torque to usable motion.

No ask yourself how many gears does your outboard have?  ONE.

It's the one gear in the lower leg that takes the crank shaft HP ( a function of RPM and Torque) and reduces it to drive the prop shaft. The reduction is typically in the range of  1.75:1  to  2.08:1. For simplicity lets say this gear is 2:1 so if the motor has a Rev range idle to redline of 700-5800, the prop would be spinning 350 -2400rpm. 

And if we are spinning a 17p prop (with no slip) the boat would be travelling 350rpm 11.3mph (18.1km/h) to 2400rpm 38.6MPH (62.1kmh) in that rev range. Your boat speed is totally gated by that one gear and the prop pitch that you are running.... but at which RPM does that engine produce its rated HP? 

And does that engine produce enough Torque in the RPM range that you need for your boating - you can't change gears on your outboard to keep the engine at its max HP (Torque x RPM) while spinning the prop at the required RPM for the speed you need. 

So for an outboard motor it is absolutely crucial in which RPM range does the motor produce maximum Torque, because we have four critical phases in boating:

1. idle to plane (hole shot): motor 700-2500rpm: Most boats are well on the plane by the time a motor is at 2500rpm  .. prop at 1250rpm 17p prop 20.1mph (32.3km/h). (For instance my hull planes at 20km/h)

In boating we need a lot of torque in this 700-2500rpm range !!!  2Stroke delivered this for years because every 2nd cycle was a power stroke. Early 4St motors borrowed from the Auto industry (with Torque optimised for high RPM designed to use gears to generate low end RPM Torque) lagged low end Torque due to the outboard single gear design for many years - the max torque was too far up the RPM range to be useful in hole shot... so the industry norm was to install a bigger HP 4st than the 2St you are replacing to keep hole shot performance. Bigger HP usually derived from bigger capacity motors and hence more overall torque at the low end. We had to oversize the 4st to preserve the Torque required for hole shot -- and then that brought in the oversized motor weight consideration.

2. Plane to midrange (ride the wave): motor 2000-3000rpm. This is where offshore boaters need torque to keep the boat on a plane on sloppy broken seas, either to climb waves or control coming down the face. Motor 2000-3000rpm is 1000-1500rpm at the 17p prop ie effective speeds of 16.1mph(25.9km/h) to 24.2mph(38.8km/h). A typical boat can't do more than that speed in broken seas - your motor needs to deliver the torque you need in this RPM range to maintain control.

3. mid range: motor 3000-4000rpm: This is typically cruising speed. The boat is now on a plane and as fishing boaties we want max economy (efficiency) and optimum cruising speed (17p prop no slip, motor 3000rpm, prop 1500rpm  24.2mph (38.8km/h); motor 4000rpm prop 2000rpm 32.2mph (51.8km/h)). If we were towing skiers we'd want more torque in this range as well. 

4. top end: motor 4000-red line (typically 5800-6000 rpm) ... at these RPM ranges  with that 17p prop you are travelling at 60+ km/h ... may be of interest to the US lake fisherman, but how many times do conditions allow Aussie offshore boaties do these speeds? But interestingly thats the RPM range at which many outboard manufacturers rate their max HP!  In my case - completely irrelevant.

So putting all these thoughts together, and setting aside engine weights for the moment, a 60HP engine of the right design may actually produce the same or more usable Torque than another vendors 70HP engine in the RPM range that you do most of your boating. You may be sacrificing some top end performance but it would be the better choice for your most common boating experience. 

BUT sadly all this analysis requires you to get your hands on Torque to RPM data for the engines you want to compare. ???? 

In my case, I searched for months and found that it actually exists in the US boating community - it seems there is a very competitive spirit still in the US and the different manufacturers benchmark competitor outboards and actually publish HP and Torque curves at trade show and such. There are many forums where avid boaties photograph and share this type of data.

Here's an example of some 150HP comparisons: 

image.png.189464bc62b874418c1a80260b18aa52.png

In the above example, the 4St Merc improved the low end RPM torque over a 2st design by some 20-30% in the early planing RPM range, by specifically building a marine 4st engine. Torque is force x distance (lb.ft, Nm etc). They created more force by increasing the capacity of the engine cylinder (more volumetric fuel to explode) and increasing the distance from the crankshaft - a bigger lever - hence generated more low RPM torque for hole shot. This is still a 4St design where each cyl only generates power every 4th cycle - it burns fuel every 4th stroke and there's the 4st fuel economy. Put simply this motor throws more metal around further from the crankshaft.  This engine in several independent tests  (Perth, Melb, Bris) on different manufacturer 6m+ FG hulls consistently delivers 4sec hole shot performance - I don't think thats too shabby against any 2st expectation. All due to the focus on delivering maximum Torque in the low-mid range RPM.

The motor also seems to generate its max Torque in the 2500-3000rpm range - right where I want it for that plane-midrange RPM performance - for broken seas (remember motor RPM determines my hull speed due to the single gear - I need to go fast enough to plane, but can't go too fast due to the conditions but I need the torque at that RPM to keep my position on the wave.)

Anyway, hope this lengthy discussion is of some help. Perhaps do some googling for the engines you are considering Merc 60CT and Yam F70, and see if you can track down a torque/rpm curve for each. Or find test cases or users and get some data points: Hull weight on water, motor RPM, speed, prop specs. 

Remember "HP sells boats/motors, but it's actually Torque that moves them".

Cheers Zoran

PS1 - some other rules of thumb, obviously a higher pitch prop needs more torque to spin it, but moving 1p between propeller pitches has about a 6% variance in speed. I've done all my calcs here on a 17p and no slip. Typical acceptable slip is 10-15%, if its more than that you need to have your set up tuned (motor height - cavitation/ventilation, size of prop diameter and pitch etc). So consider these factors in setting your prop rpm pitch to speed expectation. I can share links for these calculators if anyone is interested.

PS2 -  this same vendor (BRP) that produced the chart above has compared, Suz, Yam and Merc and has produced Torque RPM curves that are floating out in google land. PM me if you want the links - again I have only focused on the 150HP range specifically. 

PS3 - and this is off OPs topic but helps with some of the decision logic on what is usable. The chart above clearly shows the 150hp eTec is a great engine - in this comparison it may lag Torque in the planing RPM phase but produces 20-30% more Torque in the mid-range RPM - if my boating included towing skiers this would have been a contender - prior to the recent BRP announcements. But in the same breath looking at the curves it's somewhat over engineered for my planned typical boating use. Just like a 200HP 4St may be - I can't use the additional Torque to spin the prop any faster in that mid range due to hull speed/sea conditions. I'm sure this will generate debate which perhaps should be moved to a different topic so the OP original question is not polluted especially if its specific to my 150-200hp decision process.

 

I'd like to heart this post twice but the forum doesn't have that function 🤣👌💪

Absolute gold

Edited by GoingFishing
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2 hours ago, GoingFishing said:

I'd like to heart this post twice but the forum doesn't have that function 🤣👌💪

Absolute gold

You could try it this way ♥️♥️ as long as no one takes it the wrong way 😂 

what an awesome insight on what’s important re outboards & how to choose what suites, great read & cheers for that @zmk1962 👍😎👍

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3 minutes ago, dunc333 said:

one thing i did notice the merc 60 and yamf70 have the same engine displacment  of 996cc. so the yam is getting 10 extra hp through  its ecu chipping cheers dunc333

Nope!

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4 hours ago, dunc333 said:

one thing i did notice the merc 60 and yamf70 have the same engine displacment  of 996cc. so the yam is getting 10 extra hp through  its ecu chipping cheers dunc333

So the 60hp Merc produces the same displacement as the 70hp yammie !!! Real eye opening stuff there. 

3 hours ago, noelm said:

So for people who just want reliability and performance?

Think you can get all of the above plus some torque with some of the other brands 😉😉. I mean...unless u want to spend the first two hours of your fishing trip just getting to the destination 😂🤣

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Thanks all for your comments. Appreciate the input, especially zmk1962. I've always looked at torque as much as HP with my cars so what you say makes sense however there is a more limited choice with outboards (as there are many more restrictions such as boat weight, design, application etc). I found this interesting comparison:

Merc 60 = 59HP @ 5750RPM and 76NM @ 3000RPM
Yamaha F60 = 57HP @ 6000RPM and 76NM @ 4,500RPM
Yamaha F70 = 67HP @ 6300rpm and 83NM @ 5,300RPM

Also expect the Suzuki DF70A would be another good option. 

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I put an f70 Yamaha on my old formula 15 which I was running a merc 90 two smoke with. In all honesty on that boat I was still able to run at pretty much the same speeds but with far better economy of just over 3km per litre. I sold the boat after only putting 450hrs on the engine in 18 months, in that time I felt 100% confident in its reliability.

My last boat was a zodiac 550 with another F70 and once again ran faultlessly during the two years I owned it, clocking just shy of 900hrs. The zodiac was a little slower and needed carful prop selection, the tubes of the zodiac cause drag in the water but I was still able to cruise at around 4500rpm for 40kmh.

The best thing for me was the ease in which the mobile mechanic could reach fuel and oil filters etc, which reduced in time and averaged $160-$200 max per service. Unfortunately few dealers pass on the savings and go by Yamaha's estimated 4hr service time.

On a visit to the Daintree in QLD I hopped on a croc tour boat which was being pushed by twin F70's. I got talking with the skipper who told me the engines run almost everyday all day and had clocked 7100 faultless hours in under 2 years. Service costs had basically been oil filter and impellers and that was it. At 10000 hrs they remove the engines to put on their second vessel which doesn't work so many hours in off season. The company had used Suzuki but due to gearbox issues dropped them, Ive heard the same comments from our local maritime officer in regards to gear issues from the constant in out of gear changes they do coming alongside other vessels. I was advised to stay with aluminium props on Suzuki engines to reduce the wear on the dog clutch.

I now have a Suzuki which in its first 200hrs has already had several issues and parts replaced according to the service repots from the last owner. It also takes longer for the mechanic to service but generally Im very happy with it. Most stainless bolts and fittings on my Suzuki seem to be of a poor stainless quality and suffer rust, as they did on another boat I owned with a Suzuki. Just one other thing, black engines scratch very easily and show marks even from from freshwater.

Most of the commercial guys I have evolvement with in the urchin and abalone industry use Yam and Merc.

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4 hours ago, Scienceman said:

Thanks all for your comments. Appreciate the input, especially zmk1962. I've always looked at torque as much as HP with my cars so what you say makes sense however there is a more limited choice with outboards (as there are many more restrictions such as boat weight, design, application etc). I found this interesting comparison:

Merc 60 = 59HP @ 5750RPM and 76NM @ 3000RPM
Yamaha F60 = 57HP @ 6000RPM and 76NM @ 4,500RPM
Yamaha F70 = 67HP @ 6300rpm and 83NM @ 5,300RPM

Also expect the Suzuki DF70A would be another good option. 

Nice comparison.  8)

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All the theory and manufacturers supplied details are fine, but, you can't beat actually "doing it" JonD has a great example, I have been involved in 2 repowers with this motor, I don't own one, don't plan on buying one, so I am not just quoting fanboy brands, just real life factual experience.

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12 minutes ago, noelm said:

All the theory and manufacturers supplied details are fine, but, you can't beat actually "doing it" JonD has a great example, I have been involved in 2 repowers with this motor, I don't own one, don't plan on buying one, so I am not just quoting fanboy brands, just real life factual experience.

Great advice Noelm. First hand experience is more valuable than any marketing spiel.(Unless of course that first hand experience relates to a 2 stroke, then of course the owner has no idea and its all lies remember !🙃)

So how does a prospective purchaser make a decision? Theres lots of customers who have purchased Yammies and had problems, a quick search on various fishing and boating forums will find countless stories, but similarly there are lots of happy yammie owners. Manufacturing is not perfect, some engines will be born with problems. This could be said about literally any brand.

The notion that Yamaha are literally the one and only brand worth buying is so ridiculous it demonstrates clear bias.

Edited by GoingFishing
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All useful comments as experience is at least as valuable as specs. Unfortunately I wont know the outcome until it is actually fitted and propped. 

I've been quoted the F70 which has a promotional discount currently for $11K, fitted, gauges, prop fitting etc. So $1K more than the Mercury 60CT but it will be mounted with the same bolt holes, gauges will fit into existing holes (now digital), engine weight is similar, I get an extra ~10hp with a little more torque. The torque does seem to be at higher revs than the Merc so I think fitting the right prop will be essential to ensure low - mid range grunt. 

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I did have an issue with a 4 stroke merc where I turned on the battery isolation switch and didn't realise the ignition was turned, this didn't turn it over but it did fry all the ellectrics and rectifier ( what ever that is ) $1500 mistake. Not sure if this is something that would of happened from other brands but after doing it I soon found out I wasn't alone in doing it to a merc.

Unfortunately the cost of an outboard really does make you search high and low for true reports. You could quite easily look up the croc tour boat I mentioned and get it first hand from them. There was also an outboard mechanic on the Hawkesbury who serviced the house boats, when I last spoke with him he had clocked over 3000 hrs on his f70 and couldn't fault it.

Mercury do seem to be very economical and great torque, I don't want to comment on how reliable they might be long term but the two verado's that were on our new marine rescue vessel were replaced after just 12 months, another fact that can easily be verified. I can also put you in contact with a comercial operator who has had two powerheads on his merc under warranty ( he recently bought a Yamaha ). 

Most of us don't put many hours on our boats, I'm lucky that I get to drive several boats that I simply walk away from at the ramp, tourism and work boats.

 

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 to nolem are you dissputing my  dissplacement values  of 996cc f70 and merc 996cc 60 hp as i will say again all new outboards are good.these days any brand, price ,dealer location support ,and your trust in your local dealer  .no 1 thing is correct rigging of any new engine .cheers dunc333

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