2001 Yamaha Kodiak 400 Stalling Out

[Wildhorse800]

Was out riding for hours and no problem at all. Started down a grade and it just died. Pulled the side cover to inspect my see-through fuel filter and it looked empty. Pulled the hose off the carb and gas ran freely from the tank,through the filter and out the hose. Tried to blow into the carb inlet and could not. Figured either the floats were stuck or the needle valve was stuck in the seat.
Needless to say, we had to tow her out with the Polaris and load it up to get it home.
Just got the carb torn down and didn't find a single thing wrong inside. Not a single jet was plugged, no dirt,needle valve and floats were operating perfectly.

It is definitely fuel related. It sat for a while in the garage and and it fired up and ran just fine for about 10 seconds and then quit. Again, the fuel filter was bone dry. It just wasn't allowing gas to come into the carb,possibly from there already being enough inside, but then not allowing fuel to enter fast enough to keep the bowl filled sufficiently.

I am gonna rebuild it anyways. Just don't like not knowing why its happening. Anyone else have this happen to them? Usually carb troubles start small and increase over time. This thing was running great and it just happened suddenly.

BTW, I hate these variable venturi carbs!

[John451]

Sounds like the gas inlelt on the carb is clogged

[Wildhorse800]

Nope. Like I said, everything is working perfectly. The inlet "valve" you are speaking of is the needle and seat that is operated by the floats.
The inside of this carb was spotless. When the machine was new, I immediately installed an inline filter, which evidently did its job.

This is why its a dome-scratcher for me. It won't ever be truly fixed unles I know the "why" behind it.

[John451]

i was talking about the part of the carb that the fuel hose goes on. When you open the carb is there gas in it? I guess if you have a fliter there woulldnt be anything in there though... look at the boot between the carb and the motor and make sure there arent any cracks... spray some carb cleaner on it while its running and see if it revs up at all, if it does then you need a new boot

[Wildhorse800]

All the obvious checks are OK. Picked up a new needle valve set(freakin $28-had to pick up my jaw from the floor) and will be installing it later.
I'll let ya'll know how it goes.

[Wildhorse800]

Well, I'll bite the bullet and say it WAS NOT the carb. But at least I know it is fresh now.

Got it back together and ran perfect for @ 10 minutes. Gave it a quick wash, pulled it into the garage and it died, again. So started diagnostics on the electrical anf found the problem.

The wiring from the coil to the harness had been losing contact at the plug connector. It was then creating a field, using the frame as the sole ground(not good). So cut out the connector and bad ground wire, rewired and reinstalled the coil. Went out in the rain for about 3 hours without incident.

The ground wire's insulation was kinda flattened and the contact point inside the connector had begin to burn the plastic. This was my brothers and he continually used it with the bad battery and jumped it with his car to get it started.

****Lesson Learned****

If your battery is dying, pay the $$$ and just get a new one. I am sure this is what caused the problem. This quad did sit alot.

But I am happy it is working and this may help diagnose anothers problem.