Yamaha F80 Video- Can Anyone Help Diagnose?

[monkeyman41]

Rodbolt, thanks for your earlier response! Take a look at this video (turn up volume), anyone have any comments? Had service performed last week, carbs were supposed to be rebuilt?

http://www.youtube.com/watch?v=H0uVDUs52hY

Thanks to all!

 

[EAVES]

Re: Yamaha F80 Video- Can Anyone Help Diagnose?

That is a lean cough. Its in the carbs or a dead plug but i would say 100% its in a carb.
Video the boat on the trailer backed in at a ramp and see how it acts under a load and how it idles. Also ck the linkage bar that ties all 4 carbs together ck to see if it has popped off the bottom or any carb will cause the same prob.

 

[EAVES]

Re: Yamaha F80 Video- Can Anyone Help Diagnose?

Even also if the fuel has ethenol in it. It could be bad fuel. After sitting for a week or longer the ethenol will seperate from the fuel and cause carb and fuel system issues always keep the fuel treated with a good enzyme stabilizer

 

[rodbolt]

Re: Yamaha F80 Video- Can Anyone Help Diagnose?

if I try to open a video on this box it will lock up.
only two things on that motor will cause a carb spit back, a lean air/fuel mix in the intake tract or a leaking intake valve.
as valve trian isues are incredibly rare and carb trash isnt I would say try the carbs again.
and you never answered my question about the service facility.
was it a reputable yamaha service facility with technician certs on the wall or a backyardigan shop ?
the techmate tool needed to properly set the carb shutters is about 650 dollars and not all service facilities actually own one.

 

[monkeyman41]

Re: Yamaha F80 Video- Can Anyone Help Diagnose?

If you want to see video go to YouTube and search- Yamaha F80 2000 YT. I was recommended to this marina (who rebuilt carbs) because they are certified. Did not confirm certificate on wall. Thanks

 

[rodbolt]

Re: Yamaha F80 Video- Can Anyone Help Diagnose?

like I say, if I try to open a video on this box it locks down.
poor box is only about 9 years old.
wont be the first set of F carbs I have ever seen that had to be gone into several times.
the passages are incredibly tiny and can kick a techs butt if they are not ultra careful. toss in the fact that todays fuel can and will dissolve draw tubes and fuel level sender floats and it can get wild.
the dissolved resins WILL pass a water seperator and WILL NOT pass the carb passages.
dont ask how I know.
but its also why we seatrial ALL F carb jobs or at least,in your case, would run it up with test wheel YB1624 and look for an RPM of about 5200-5500.
this new fuel blend has made me hate F motors with carbs.

 

[EAVES]

Re: Yamaha F80 Video- Can Anyone Help Diagnose?

If your doesnt have a 10 micron Yamaha fuel/water seperator on it put one on it and Yamaha higly recomends one also

 

[Kanadakid]

Re: Yamaha F80 Video- Can Anyone Help Diagnose?

Rodbolt / Eaves, I thought that fuel stabilizer would keep the ethanol from dissolving the tubes and getting into the engine. If not how do you protect a carbed yam 4 stroke ?

 

[EAVES]

Re: Yamaha F80 Video- Can Anyone Help Diagnose?

There is no cure for the seperation of the ethenol from the gasoline the only thing you can do is run the engine often or drain the carbs . I have done tons of the carbs and others but the ethenol is a killer What stabilizer are you using ???

 

[EAVES]

Re: Yamaha F80 Video- Can Anyone Help Diagnose?

http://www.starbrite.com/sproductdetail.cfm?ID=1537



That is the link to the stabilizer i have had better luck with or the Yamaha brand

 

[Kanadakid]

Re: Yamaha F80 Video- Can Anyone Help Diagnose?

Well I never winterize my engine because I run it all winter long. I usually go no longer than 2 to 3 weeks without running it all day or 1/2 tank.

I always have stabil in it to keep the fuel fresh. However if you and/or others think there are other fuel additives that work better I would definitely use it.

I also installed a fuel water separator at Rodbolts suggestion. Never had any water in the secondary fuel filter.

So many have had carb issues and I want to do everything I can to prevent it.

Eaves I have a post about valve adjustment on a 2003 F90, can you take a look.

Thanks

Kid

 

[EAVES]

Re: Yamaha F80 Video- Can Anyone Help Diagnose?

The stabil i found (for me) isnt worth buying and the Starbrite brand does help more than any others. If you are using the RED sta bil it for sure will do nothing for ethenol and the BLUE sta bil is for ethenol but i think it doesnt do any better than the red but i would really think about changing over to the Starbrite brand and let me know how it works for you and you need to run the engine weekly 2-3 weeks is long enough for the fuel to seperate JE

 

[Kanadakid]

Re: Yamaha F80 Video- Can Anyone Help Diagnose?

Eaves to be quite honest I wouldn't know the difference between the two. The only thing I know is I have kept red stabil in the tank and try not to let it sit to long between runs. I have a fuel water separator too. So far no problems with the carbs.

Why, I have no idea. Perhaps I have run the engine enough over the years to keep the fuel fresh enough , maybe the stabil had nothing to do with it.
I really have no way on knowing except that I haven't had any problems. Also I keep the boat in the garage.

Thanks again, the guys on here have always been great and I am glad to ne back on.

Kid