Need help whit the "automatic choke" on a F50 2000 model 4stroke

[Eirikhau]

Where in the hell is Rodbolt? He needs to put down the guns and bottles and give us a hand here.

I don't have any personal experience with the OP's particular model but the name Rube ****berg comes to mind when inspecting the parts catalog and service manual with respect to the fuel system. I suspect that Yamaha employed ole Rube to help them with the design and fabrication of their motors.

From what I can see this motor has a prime start device and a solenoid for choke plates. And the solenoid is activated when the starter is engaged, not when the key switch is pressed in or a choke toggle switch is activated. And then the solenoid power comes through some sort of thermoswitch.

I would have presumed that the thermoswitch is normally closed, allowing electrical power to flow to the solenoid when the motor is cold but preventing it when the motor is hot and choking is not needed, but the SM indicates it operates exactly like an over temperature thermoswitch. If the motor is cold and the switch is open then how can current get to the solenoid to activate it?

And what does the prime start do? It is not configured like a typical prime start component.

See wiring diagram below. Strange, just strange. Maybe Rodman can give us the theory of operation.

You are completly right, it goes trough a thermoswitch, ill try and explain the wiring as best as i found out.

From the starter relay theres a wire, that wire is splitt in two. one brown wire and one blue. the brown wire goes too the key, im guessing thats the puls signal that tels the relay too release voltage too the starter. the blue wire goes over too a thermoswitch in the rear of the engien, and from there it goes back and too the solenoid.

i can see that when i start the engien the shaft in the solenoid moves and the engien starts with ease everytime. but, the idling is too high, it stays on around 1900rpms for a minut or two, and then the rpms increases quickly.
but, if i hold down the levers in the picture here earlier the engien runs at around 8-900 smoothly and will run like that for as long as i hold em down.

the motor has just been laying in a garage 2months before i just bought it, and prev owner says he never has had any problems whit it(ofcourse he says that, but cant prove him wrong so have too take his word on it)
i installed it on my boat, and the rest you guys know.

i took it out for a test run the first time, hoping that the rpm would calm down as the engien got hot, but when i put the throttle in drive i got way too much low speed, i had too drive like a maniac inbetween the boats in the harbour, and the gears wherent too happy about having too go into gear in that rpm anyways, when i got the boat out too sea i put it on 4000rpms and it worked wonderfully, no bad sounds and accelerated nicly, and keept 4000rpms for as long as i wanted. when i gave it full power i got around 5700rpms, and again worked wonderfully. when i was heading back too the harbour i put it back at the least power i could give it and i gaind too much speed, and was a rocky ride in too the boat area again. and when i then put it in neutral the engien revved up fast. and had too turn if of fast.

i see here that theres supouse too be a spring on the inside thats keeping the levers down, but why then when i added voltage too the solonoid from another circut was that keeping it down? shouldent it pushed it up if there allready was something holding it down? ill try add more pictures, and hopefully a short film clip so you can listen too the enigien and see for yourselfs

again, cheers all for all the help so far

[Eirikhau]

cant i add a film clip here ?

[99yam40]

I have a feeling that Yamaha just messed up the way they should have showed a N.C. switch when cold.

Are you saying the prime start wiring is not as it should be or is it the way it does the fuel that you say is not the same as other motors?
I guess #6 is the rectifier/regulator and the G/W should feed 12 Volt+ power as long as the motor is running from what I am seeing, so that should be the same as other prime start systems.

[99yam40]

What are the butterfly valves? is that what i am holding down with my finger there? iv adjusted the throttle cabel, but the leveres that im holding down is the only thing that is adjusting the rpms, it should stay down towards the rpm idling screw?

There should be 2 sets of them one set for throttles farther inside the carbs and another set for the choke on outer part of carbs.
Have you looked inside the throats of any carbs before to see what is in there?

Hold on now are we sure this motor has a choke?
I was just going off of what the OP said.
How about you Boscoe99

[Eirikhau]

Guys, check this out : https://youtu.be/z_S5BBDctIM

there you can see and listen too what the problem is

iv uploaded a short film, i just started the enigien there, and those are the leveres i mean the solanoid(choke, prime) is supose too adjust?

sorry that its upside down filming, but my dear father has no idea how phone works.....

[Eirikhau]

i have not looked inside anything, nor have i opend any carbs.
as i understand the carbs are sensetiv parts that requires some knowledge of motors before messing around whit em.

i sadly have a very low understandig of motors and just doin my best whit that i can manage too read and figur out whit my own eyes....

thats why im writing on this forum, so maybe i can get a better understandig of whats wrong and how i can fix it. i just purchased this so im quite keen too test it out as you may understand

hopefully you will get a better sens of things once you watch the movie.
combine poor english and poor understanding of motors and theres me trying too write so you guys can understand what i mean and what my problem is:P

[Eirikhau]

after talking too someone who has the same enigen as me, it seems as the wiring is correct. its supose too be connected too the starter relay, and its supose too only be in use as i start the enigien, but then why are the acting like that? why will they not stay down on their own?

because when i put voltage extra too the choke soliot it keeps the levers down.... but when i cut the voltage on it they just wonder of by them selfs... im starting too think maybe its freaking backwards? when voltage comes too the soloniod its supose too open up for more air/fuel, but mine closes when it get voltage and opens when its not getting voltage? .... .

[99yam40]

I will repeat what I wrote before
There should be 2 sets of butterflies in each carb one set for throttles farther inside the carbs and another set for the choke on outer part of carbs.

the choke ones should close off when energized and open when not energized.
The other set is suppose to control RPM

You may need to have someone with the proper knowlage have a look to see what is going on

You can always go have a look at the other motor with the cowling off to see how it operates all the linkage when started

[Eirikhau]

gottcha, but is the only way too adjust idling rpm the little screw down at the botom of the carbs or is there any other way?

[rodbolt17]

I was waiting on Boscoe to provide the harness diagram.
been a while since I delt with the rube****berg set up of the 2000 and older F/T50'

I can tell you its the most complex system of ANY manufacturer and without a manual and a clue its hopeless.

its a two stage ckoke/primestart device.

one stage the round one, gets voltage from the stator to move the lever.

the square one gets a voltage though the thermoswitch,if hot or cold, and gets voltage when cranking.

then ya gotta have the dashpot and a couple other adjustments correct or your sunk.

like I said.
its rube****berg at best and my neighbor has one.

[Eirikhau]

I was waiting on Boscoe to provide the harness diagram.
been a while since I delt with the rube****berg set up of the 2000 and older F/T50'

I can tell you its the most complex system of ANY manufacturer and without a manual and a clue its hopeless.

its a two stage ckoke/primestart device.

one stage the round one, gets voltage from the stator to move the lever.

the square one gets a voltage though the thermoswitch,if hot or cold, and gets voltage when cranking.

then ya gotta have the dashpot and a couple other adjustments correct or your sunk.

like I said.
its rube****berg at best and my neighbor has one.

awsome....
so, what you think when watching the movie is wrong?
should i give up and call it a night and end the season all pull the boat on land and get it too a service shop? (3 weeks waiting time there because of summer vacation)

[Eirikhau]

because these are the screws that adjusts the ideling rpms right ?

[TownsendsFJR1300]

If you have to slam it into gear at 2,000 RPM's, IMO, I'd park it before you need a new lower unit.

Its really not safe for you running it that way..

That one spring, as I posted earlier (and quite obvious), someone dinked with it and it certainly doesn't belong there/and like that..

[Eirikhau]

yeah... i have too slam it into gear, and since rpms too high i get a very high speed while driving slowest, and in the harbour theres alot of expensive boats and a tight fit getting trough there, and the gears are crying like hell when i slam it.... so im guessing im calling it and pulling it on land and getting it serviced.


Cheers alot guys for all your help i would still be over at the enigen scratching my head and cussing like a madman if you hadnt helped me along

hopefully my next thread will be topic " dream day at sea, great fishing too" .

alltho thinking where i live im guessing 6degrees celcius and rain and a small hurricane.....

but again, cheers all who have helped

ill keep you updated when its been on service and they can tell me what was wrong

[TownsendsFJR1300]

Please post back when she's fixed and how involved it was.

Hopefully, they didn't screw the whole system up.

Good luck..