gy6 fuel issues By rosszx10r (Read 1,052 times)

[rosszx10r]

hi

i have had this Peugeot sum up 125 for a few months now had to rebuild the engine but now I'm all back together I'm getting no fuel into the carb. If i pull off the tube from the tank to the pump fuel pisses out. Turning the engine over and nothing is getting sucked in, I checked that the vacuum pipe is attached to the rear yet still nothing. I know the bike starts as if i spray quick start into the carb she starts straight away. do i need a new pump?

[Bashan]

Try bypassing the pump by running a line directly to the carb from the tank. If it starts you have a bad pump. If it does the same thing it's the carb.

[rosszx10r]

wow didnt think of that :0

[rosszx10r]

ok tried that no luck time to clean carb?

[Bashan]

Yep, probably the float valve is dirty and not letting the gas in, or the main jet might be plugged up.

[Bashan]

Hey, if your tank is lower than the carb that test won't work. What I do in that case is I use an outside tank and run a line. Or you can pull the feed to the carb from the pump and crank the engine to see if gas comes out. Sorry, I was thinking gravity fed pump.

[rosszx10r]

hi an update looked at carb cleaned wasnt really dirty, i had an carb tried that two still no luck?

[Alleyoop]

Ok, one question do you have a VACUUM LINE going to the Fuel Pump(tank lower than carb) or Petcock(tank higher than the carb) and it is not cracked or old, if good take the fuel hose off the carb and put it in a container and crank the motor over.
If nothing comes out then check your fuel filter it may be clogged, if good then its a bad petcock since you already checked fuel flow from tank to petcock.
Alleyoop

MAKE SURE YOU HAVE THE LINES CONNECTED RIGHT ON THE PETCOCK:

[Bashan]

How did this ambiguity start up with Chinese scooters? Maybe because they don't speak English? Alley is 100% correct, he showed you a vacuum fuel valve or petcock, it is more often than not called a fuel pump. It does not pump, it opens up when vacuum hits it and that happens when you crank the engine. So if you have that the bypass test would work because they only use the vac fuel valve with gravity feed systems.

This is actually a vacuum fuel pump, it pumps gas when it gets a vacuum from the engine. The bypass test will NOT work with this pump and the tank is lower than the carb. The same applies to an electric fuel pump:

The vendors need to quit listing the vacuum valves as pumps, they do nothing of the sort.

[rosszx10r]

OK the tank is higher than the carb. OK so if I pull the fuel intake off the fuel flows out freely. If I pull carb feed off and turn engine over the fuel drips out not a lot really but then I don't know how much should be. I put a vacuum pipe on the rear as shown still drips out same speed. I connected fuel feed from tank straight to the carb didn't start?. But odd thing is if I spray easy start into the carb from the rear starts straight away.

[Alleyoop]

Cool, so after it starts and no problems and it keeps on running and you can ride it, then I think you ought to check out your ENRICHER on the carb. It may be stuck in the extended position and not feeding it extra fuel for cold starts.
Alleyoop

[rosszx10r]

No as soon as I stop spraying easy start bike cuts out

[Bashan]

Sept 12, 2014 11:15:17 GMT -6 rosszx10r said:

OK the tank is higher than the carb. OK so if I pull the fuel intake off the fuel flows out freely. If I pull carb feed off and turn engine over the fuel drips out not a lot really but then I don't know how much should be. I put a vacuum pipe on the rear as shown still drips out same speed. I connected fuel feed from tank straight to the carb didn't start?. But odd thing is if I spray easy start into the carb from the rear starts straight away.

There's nothing odd about it, that is acting as the fuel. So if you connected the tank directly to the carb we know fuel is getting to the carb. Crank it over a few times and then pull the plug. See if it is wet and smells like gas.

[Alleyoop]

Cool, so only spraying keeps it running, which means the motor is not sucking in fuel from the carb.
So take a picture of your carb area and hoses especially the left side of the carb where the adjustment screws are at need to see what carb adjustments are on that thing. If it hasn't been running for a while months then the carbs jets and passages may be clogged with varnish.
Alleyoop

[rosszx10r]

OK will take a few pictures tonight