Re: 94 Yamaha 700 Stalls after 10 minutes
Ok, you might be going the correct direction. When diagnosing try to always completely eliminate one thing before going to another to eliminate errors.
I will try to ad some supporting info with the advise so you will understand why and what you are doing.
The fuel system is for the most part a closed system. It does not have a vent.
The line is a air inlet line and it has a one way valve on it so when the fuel in the tank is depleted from usage it can be replaced by outside air. If this air was not replaced the vacuum inside the tank would over power the meager little (diaphragm style) fuel pumps these rigs use.
Now that being said. Run test the ski until it dies. Remove the hood and put a hand on the tank. With your hand on the tank remove the filler cap quickly. You might feel the tank expand if there was a suction condition. Don't worry if its not obvious and you can't tell, because if it was you will know soon enough. Re-install filler cap and if it was vacuum locked you should be able to get it running now. Of course it will only run a short time again.
But what ever info you learn from this you must back it up with a manual test of the valve. I have the place and I would just do that first, you can also.
Access the ( AIR INLET ) line valve. It should be close to the tank on the line and look like an old school motocross bike fuel filter.Sort of (cone shaped) and the line won't go toward the fuel filter it will go towards the area the steering cable exits the body.
If its a Yamaha or quality replacement it should have an arrow on it and always pointing towards the fuel tank. you can remove it and with a vacuum tester you should only be able to pull air in the direction of the arrow. If you don't have a tester you can probably get the air to flow by sucking on it. If there is any problems with it just replace it they are cheep.
As for fuel filter they should be replace annually but never are so you should get one, but don't install it until you know the air inlet is ok. They are a few $ more but the Yamaha ones are the best way to go.
Try those and if they are ok there is a possibility of carb. problems, but they don't usually run fine for ten mins. first.
If all is ok then I would start towards the automatic shut down system for overheating protection, but first things first.
Sorry about the long post, but a little reading never hurt anyone
