Throttle problem on Yamaha 100 4stroke 2001

[tonn's))]

Hello. Yamaha 100 4stroke 2001 hadn't a very well throttle...
2 cylinders don't work.
I have removed and replaced all carburetors, everything is OK.
Fuel tank, filters and fuel are excellent.
I made a synchronization of carburetors.
It seems be the throttle sensor... I haven't the tension values of this one at throttle to adjust it
And with witch wires i have to connect ??
Escuse my bad english and thank you in advance

[rodbolt17]

TPS wont affect just two cylinders.
have you tested spark and compression on all 4 cylinders.
on that engine it uses two waste spark ign coils triggered by two pulser coils.
ign system is 12V TCI.
1 and 4 fire simultaneously as do 2 and 3.

[tonn's))]

unfortunetly i haven't the special equipment to check compressions, but the engine seems to run very well after idle !
I checked ignition on the 4 cylinders, no problems !
Problem provides from cylinder 2 and 4 :
When i pull wire out of igniters from cylinders 2 and 4, nothing change, and the throttle regime still be 950 rpm.

However have you got the tension values TPS in throttle to begin on correct basis ?

[Sequoiha]

You say you syncronized the carbs, this must be done with a manometer, (vacuum gauges), if it wasnt then it isnt right, and Like Rodbolt said, tps wont have any effect on 2 cylinders, F100 carbs are very tedious,

[99yam40]

Good Compression, spark, timing of spark, and proper fuel ratio are needed for each cylinder to fire properly.
If you do not have the proper equipment to test the simple things (Compression, spark, timing)then find someone that does.
If all is well with that then deal with the fuel

[tonn's))]

Ok , thank you for your advises i will do that !
I made carburetor synchronisation whit the specials equipment... Now I had to check compressions and timing of sparks.
An other question, i tested my boat today, open 5 meters with the yamaha 100hp 4stroke... I have a 13*19k propeller, and the engine get max rpm very fastly, 6200tr.min speed 65km.h (40 mph)
What kind of propeller wille be better ? 13*21 or 13*23

Thanks for all

[99yam40]

Sounds like pilot jet/passages have a problem or carbs are not adjusted correctly, as it would not run that good with only 2 cylinders firing.
Maybe small vacuum leak?

It would be nice if you could try both the 21 and the 23 to see how they work.
Might look here to see if you can find something close to your set up and see what prop they were using. http://www.yamahaoutboards.com/owner...ance-bulletins

[tonn's))]

Now my engine works perfectly !!! the problem provided from the starters ...
When i remove and replace them, i didn't engage very well the small needle in it place... consequently,the opening which usually is open only when engine is cold stayed all times open.
Very bad for regulation near idle... and mix too rich. The reason why 2 cylinders only firing

I commanded a 13*21 propeller and i test it as soon as possible.
Thank you for your advises