2 versus 4 stroke outboard motor?

beachboy61, Aug 21, 3:16pm
I'm interested in a 5 m fibre glass boat which has a 2012 x 90 hp two stroke motor.
I know the current trend is to go for 4 stroke motors, but due to the 4 stroke motor weight Ii could only fit a 70 hp 4 stroke motor in the boat, which to me isn't powerful enough and would affect the resale value.
Thinking of resale value, I'm wondering how much more I'd loose if I sold the boat with the two stroke motor in say 5 years compared to a 70 hp with a 4 stoke motor?

budgel, Aug 21, 3:41pm
That's very hard if not impossible to figure out.
My suggestion is, see if you can find some examples of each type for sale at present and take note of the difference in sale price. (The more examples the better.)
Work out the percentage difference between the types and project it forward.
The drawback with this method is that you dont know the original purchase price of the examples for sale, so you arent getting a grasp on the depreciation, only the difference in sale price.

Are you sure the 70hp wouldnt be powerful enough? I think they have a fatter torque curve than a twostroke, which might surprise you.

martin11, Aug 21, 3:44pm
70hp four stroke should be okay on the 5.0 boat whos make of boat ?

serf407, Aug 21, 4:34pm
In 5 years time even a replacement 90 horsepower 2 stroke is likely to be heavier when more tech and anti-pollution equipment is added to the outboard.
https://www.evinrude.com/en-US/e-tec.html 90 hp 140 kg 2 stroke

and other 90 hp outboard - 120kg 2 stroke

sr2, Aug 21, 4:36pm
Just run one motor instead of 2.

The 90 hp 2 stroke Yamaha's each weigh 126 Kg dry.
A single 200 4 stroke Yamaha weighs 221 Kg.

bwg11, Aug 21, 4:50pm
I had the same decision back in 2010 when I bought a Haines 485. Choice was the Yamaha two stroke 90 or the four stroke 70. Chose the 90 which was significantly cheaper. No regrets. The four stroke would be quieter, probably use a third less gas and have significantly less bottom end grunt. Apart from that the Yamaha two stroke 90 is recognised as a very reliable engine which mine has proven to be.

martin11, Aug 21, 4:53pm
? Has only 1 x 90hp on the boat now .

sr2, Aug 21, 5:27pm
Woops, alz-Simon's disease strikes again!

wind.turbine, Aug 21, 6:28pm
2 stroke has way more go in it, if you are going over bars all the time or in rough seas then the 2 stoke is the one to give you power when you need it.
if you are concerned about fuel then what about looking at an etec? better fuel economy than a 4 and 2 stroke and has the power like a 2 stroke

s_nz, Aug 21, 6:48pm
Depends what you are going to do with the boat. The 90hp 2 stroke will be far better at pulling skiers out.

But if you don't need that fast hole shot, a 70 4 stroke would be nicer. Fuel consumption is much lower, they are quiter, easier to start, and you don't get 2 stroke smoke. Also note that branded 2 stroke oil is fairly expensive.

As somebody else noted, direct injection 2 strokes such as "etec" give 4 stroke like fuel consumption in a 2 stroke engine.

m16d, Aug 21, 8:09pm
2 years ago I changed my 2 smoke Yamaha to a 4 stroke of the same power.
The 2 smoke defiantly has more getup and go from a standing start, but the top speed is exactly the same for both of them.
The 4 stroke weighs half as much again,and uses about 20% less gas.

With the 4 stroke, turn the key and it's going.

bwg11, Aug 21, 8:47pm
Another thought is that with the current environmental posturing and signaling by our Green coalition the banning of 2 strokes on our waterways is far from impossible.

clscmg, Aug 22, 4:31pm
Just remember you cannot let a two stroke sit around as the oil will glue up the carb - you really need to start it up every week or so, its hard in the middle of winter but it needs to be done.

martin11, Aug 22, 4:34pm
Most 2 stroke out boards are oil injection now and it is the petrol that actually goes stale and gummy unless you put some fuel saver in the last tank load before you park the boat up for the winter .

paul861, Aug 23, 6:36am
rubbish. just run the carb dry before you put it away

paul861, Oct 18, 3:48pm
best fuel saver ive come across is 2 stroke oil . I put a capful in every tote tank before I fill it never had a problem .