twin motors

[Noelm]

this is for anyone who has ever owned twin Motors, have you noticed that both Motors are never the same as far as running, starting or anything else is concerned? I have had lots of Boats with twins, OMC, Yamaha mostly, and without exclusion, none have been the exact same, like one will need full warm up and choke to start, the other half warm up, or one will idle for hours, the other is cranky, my current ones are an example, the port Motor is a gem, the starboard one has never been as good! any thoughts?

[freddofrog]

Boats/motors are like people, either naturally left or right handed, but rarely equal with both.

I have no idea Noelm, mine is the same, I've had more issues with my left motor (gummed up carby) than the right. No idea why it would effect one and not the other, both exactly the same, used that same amount and in the same conditions etc, go figure???

[Noelm]

I had a pair of Yamaha 90's and one Motor if you even just thought about choke or warm up to start it, you might as well give it away, it would never start, you had to prime the bulb and turn the key, but the other one, full warm up, full choke and away she goes, both the same Motors, but so different!

[frankgrimes]

Tolerances in motor components can vary quite dramatically, resulting in the differences you experience in one engine vs the other.

Mick

[griz066]

Tolerances in motor components can vary quite dramatically, resulting in the differences you experience in one engine vs the other.

Mick

Thats a very broard statement could you be a little more specific for us dumb bunnies out here. I would have thought motors that are factory made to specs would be identical to each other.

[frankgrimes]

I would have thought motors that are factory made to specs would be identical to each other.

Motor Components are mass-produced and have a given tolerance - Each is identical within that tolerance....the tighter the tolerance, the more difficult the task, and obviously the more expensive it will be.....therefore the components used must be at a price to ensure economic viability.

Then think about these mass-produced components, each falling within the "acecptable" tolerance....these variances give way to motors coming out of the same factory, with supposedly identical specs, performing differently.

[Chimo]

Hi Noelm et al

Yes I too have twins and one runs just sweet; the other one the same just a bit sweeter.

On full song and trimmed out their tune compliments each other and come to think of it, its much the same at mid revs too.

They both blow heaps of smoke at start up but the tech has convinced me that this is a good thing so no use complaining.

And they both seem very tolerant of the fuel variability that one gets from the pump these days too.

I haven't named them yet but maybe I'll get the girls onto that as a chore over Xmas.

Cheers
Chimo

[Dean1]

Ive owned 2 pairs of 2 strokes and i would say that they did behave differently to each other. But my new F60's are a different story, they both start straight away and run the same. Fuel injection is a brilliant invention ;)

[PinHead]

previous boat had twins..and they were twins..both purred together and ran beautifully..ty mr Volvo

[finding_time]

Got to agree with Dean,Noel! When you finally;D get yourself a pair of 4's you'll get 2 motors that run the same!!!

[skipalong]

new technology would make a big difference wouldnt it

[ffejsmada]

Yeah, I had twins at one stage, years back and loved 'em.
I learnt a valuable lesson early on with the fuel being sucked out of the one tank supplying both engines. Never again.

Only thing that used to gripe me a bit was to get them singing along in harmony, one throttle was about a centimetre away from the other.

There's no better sound than two outboards singing in perfect harmony!

[Grand_Marlin]

There's no better sound than two outboards singing in perfect harmony!

That is so true - especially the OMC and Yamaha V6's.

I think the carbies are the culprit re: the differences in attitude bewteen motors.

It just adds character to the boat ;)

Cheers

Pete

[sempre]

I have had twin engines for a year now , done about 140hrs they look the same and run the same .

[Noelm]

Oh Yeah a pair of V4 OMC's at high RPM in sync is a sweet sound, Jesus I think I am getting a woody just thinking about it!!!