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

[Eirikhau]

i heard back from the mechanics .... sadly......

They dident find out whats wrong whit the idle rpms because they dident like the way the enigien shaked when started.... turns out one sylinder is dead...
they messured the pressuer on em, 3 of em was messured too 7.5, but the last one was messured too around 2.4 ......

they looked at the valves and they where fine, so either a crack in the motor, or some pistonsrings or somehting is gone....

sad day for bought me and seller, he assured me the engien was fine but it probably needed a service, because it was a while since he had it serviced.... turns out its far from fine.....

[rodbolt17]

find real mokanics that use approved test procedures and tools.
a leak down test would tell you rapidly if it was a valve,gasket or ring issue.
all it requires is spark plug removal and your ears.

you simply sometimes cannot look at a valve that's still installed and tell if its sealing or not.

[Eirikhau]

Yeah, so taking the boat too a diffrent mechanic, just talked too a company that only do repair and service on yamaha, and they had a hard time belving that the comp was too low on it.
after how i drive it, i shouldnt be able too get any speed on the boat if a cylinder is gone.
and they said that on that model the cylinder was on the bottom was very hard too messure because of it location.
so they recomended a mechanic near me that i should go and get the boat checked out there before i scraped the engien.

[TownsendsFJR1300]

I doubt you'll be trashing the engine.

It could be as simple as a valve adjustment (too tight). Broken blocks are pretty rare..

This is the leak down tester I use; https://www.otctools.com/products/cy...age-tester-kit

Do a search on You Tube and get a general idea on how it works. Its really very simple and will narrow down the compression issue real quick..

[Eirikhau]

The end of the history.

So it took 2 diffrent mechanics and much testing by myself.
The first mechanics worked on the boat for 4 hours and found out That a cylinder was broken, wich in turn they recomended me sell the engien in parts...
After tips from you guys and talking too a Yamaha workshop i found out i needed too Get a second opinion, wich i did from a mechanic that Yamaha recomended . They used 2 hours and fixed it, the carbs where realy messed up in adjustment.

Now iv used the boat, and it works perfectly, when cold it idles around 1000-1100 rpms, so when i used it and got it hot it idles around 700-800rpms.
And i can drive in the harbour at slow speed

So happy ending too the story
And thx alot for all your help, much apriciated

[TownsendsFJR1300]

A good mechanic is worth his weight in g0ld!!! Their just often hard to find..

Congrates!!

[boscoe99]

Why are we prohibited from using the word ****, as in ****ilocks?

[99yam40]

I do not know, but it has been that way for years and some other simple words get the same treatment. like a very young adult or older child (****)

Something to do with searches on the net? who knows for sure,

I wonder if Silver or platinum should get the same treatment

[TownsendsFJR1300]

Well $hit, I didn't do that... dumb....

[rodbolt17]

like I said, that system was a rube **** berg set up.
it went away in 2001.

in my area that motor was never popular so I only see a few a year,sometimes not even that much.

mechanical problems with cyl sealing are rare.

most of my work is 150 and up with twins.
here lately its been F250 and F350 block and head replacements and valve jobs on F350's.

[JonasJo5]

Bumping on old thread...

I have a Yamaha F50 1998...my engine starts easy and stay good on idle 800-900rpm.
My problem is when I accelerate quick it always die. I have to go slowly up to 2500-3000rpm and then its working fine.

When I push the choke rod, then I can accelerate normal and the engine doesnt die. Any suggestion?

As said before in this thread, the stator coil only activates during startup and not when itīs warm. Why is the stator coil going through the thermoswitch on backside of the engine?

Please, see video where you also can hear some noise. I was not able to push down the choke rod cause I had the mobile in my left hand

https://www.youtube.com/watch?v=c9FjqO8JZRI

[boscoe99]

Bumping on old thread...

I have a Yamaha F50 1998...my engine starts easy and stay good on idle 800-900rpm.
My problem is when I accelerate quick it always die. I have to go slowly up to 2500-3000rpm and then its working fine.

When I push the choke rod, then I can accelerate normal and the engine doesnt die. Any suggestion?

As said before in this thread, the stator coil only activates during startup and not when itīs warm. Why is the stator coil going through the thermoswitch on backside of the engine?

Please, see video where you also can hear some noise. I was not able to push down the choke rod cause I had the mobile in my left hand

https://www.youtube.com/watch?v=c9FjqO8JZRI

Why?

Is it too hard to start a new one?