Smaller OMC's?

[hevysrf]

I'm currently running a 2000 two cylinder 40 hp Johnson on my 16 ft kencraft skiff. The previous owner said carb jets were upgraded to the 50 ones, internet lore says that makes it a 50. Performance is marginally acceptable. Turning a 15p, vro working.
There is a 2000 Johnson70 available locally, 3 cylinder. It's not as corrosion free as my present one, running premix with vro pump still in place.
Will the be a really big difference in performance if I mount the 70? Which is considered the "better" motor? Would either of them be worth a rebuild?
Keep in mind I'm not a racer, but it would be nice if I could pull a skier.

[phillnjack]

there is a massive difference in power and torque between the triple and the twin..
your 40 is just a 40 with bigger carbs, what about the exhaust tuner , the porting etc ?

the three cylinder 70hp will have twice the torque of your motor and the top end will be about another 15mph maybe even more.
the 2.42 ratio allows you to swing bigger diameter props upto around 13.5 x 22 .

if you want to pull a adult skier then completely forget about the two cylinder, its not got the power by a long way.

I have a pig of a boat for top end speed and ive got the 1996 70hp ( same as yours) and the pull away is incredible.
this will easy pull up two people on twin ski's or a fat ( me ) mono skier. with a 13.5x 15.
normal adult about 12 stone the 17 pitch will rip them out the water
the 2 cylinder would no way get my fat arse out the water without a real struggle.

the 70 will swing a 21 pitch at 6,000 -6200 rpm and get you properly set up for a ski-ing with a 15 pitch.
to ski as I say use the 13.5x15 and that will give you around 37mph top end. plenty enough for a skier.
the 21 pitch will put you at around 46-47 mph at 6,000rpm, you might get even more rpm than me being different shape hull.
the weight is a lot more on the 70hp as its 250 pound.

if thinking of buying one make sure the compression is around 140 plus per cylinder, a good one is 145 plus on all 3.
check power trim for any signs of leaks and check the 2 smaller rams for corrosion 9 they are expensive.

as for fuel pump, pre-mix is best and safer option, when the vro fuel pump does fail, get old style small fuel pump and never have to worry.

both motors are well worth rebuilding, and the year 2000 70hp is one of the last made of the best and most reliable 3 cylinder motor ever made.

I have had mercs and Yamaha 3 cylinder and I prefer the evinrude/johnsons. merc is much easier to get parts for they are every where.

the 70hp will have quick start and fastrak power trim, they realy do start quick, and can easily be started with a rope if the battery is not enough.

thats only my opinion on them,
with a 16ft boat I would go straight for the 70, with a 40/50 your asking a bit much from it. especially it being a year 2000.

[olboatman]

I would agree with phill as the tripple makes wayyyy more power and torque and the 40 is not a 50 with just a jet change. Gary