grandkids carbide 150

[dyno]

Hey guys, new to the site, lots of good info. I need some help, the grand kids have a kart that their dad bought new. They rode it for a good while and then it would no longer start. Having a general backround with automotive work years ago I was asked to look at it. I found it has fire and will run if you put fuel in the intake track. It does't appear to be getting fuel to the carb. I replaced the fuel filter still nothing. What is the function of the valve on the bottom of the tank? Is it some type of pump that uses intake pulses? They also had holes in the tube that goes from the carb to air cleaner. Does this have to be sealed to function? Sorry about all the questions, just trying to fiquire out what does what and why.

Thanks, dyno

[ckau]

The valve under the tank is a vacuum actuated valve. vacuum from the motor opens the valve to allow fuel flow. There's two hoses off that valve, one is the fuel leading to the filter, the other is from a vacum source. The vacum hose may be T'ed into other hoses depending on the particular system but they ultimatly lead back to a nipple on the side of the intake, between the head and carb. This nipple is the main vacuum source. The valve is a safety thing so fuel doesn't flow when the motor is shut down. It's also very undependable and prone to failure. Most, when it fails, replace that valve with a simple check ball type manual shut off. The other hose you speak of is a vent hose off the carb dumping back into the filter to pass EPA regs.

[dyno]

Thanks for the quick response and the great info, I will replace the valve ASAP and from what I can gather expect that will cure my fuel supply issue. If it does'nt I'll go to the next logical step and pull the carb apart and make sure its clean and the needle and seat are functioning properly. Again Thanks.

[bear]

Welcome to the site, and we always like to help if we can!

[SLESTAK75]

Welcome to the site. I can say that if ethanol gas is being used there is a good chance of parts in the carb needing cleaned. If at all possible 100% gas is much more friendly to these little engines.