2012 Stella 4t 150 stalling when low-ish fuel

Dystronic · Post by **Dystronic** » Tue Jun 09, 2015 5:27 am

when the tank is about 1/5 full, scooter will stall after stopping vigourously, or climbing up/down steep hills. I assume the fuel is sloshing/pooling at a point away from where it can reach the intake hose to the carb. At this point i usually switch to reserve and hit a fuel pump, but it makes fillups more frequent. Is this a known issue or one of those 'just deal' kind of things? I already checked the line to from the tank to the carb for a gooseneck and found none. It's just a little alarming when you have to slam on the brakes to avoid a hazard and the scoot sputters and dies under you seconds later. Sorry if asked and answered, I didn't see it on the first page of results and its easier to ask than spend a 1/2 hr drilling down.

ArgonV · Post by **ArgonV** » Tue Jun 09, 2015 4:49 pm

Yes, at 1/5 full I have the same symptoms. From all I have read and asked about this is normal and that last bit is for the reserve. When you flip to reserve, it will burn all of that gas down to an empty tank.

As soon as it start to sputter pull the clutch in quick and flip the reserve tab.

I think the reserve amount is .26 gallons...

jmer1234 · Post by **jmer1234** » Tue Jun 09, 2015 11:27 pm

Personally, I discovered that the reserve on my Stella is a little under half tank. Basically, if the fuel level is below the top on the plastic screen column around the pickup tube, you are in the reserve. I didn't understand this until I replaced my petcock because I couldn't figure out why I was stalling with half a tank, and discovered that the 'snorkel' pokes almost all the way to the top of the screen. I thought it maybe went a quarter to half way up into the screen. I'll try to diagram below:

___________ Top of tank

____
| || |
| || | Pickup tube inside screen column
| || |
| || |
__| ||_|__ Bottom of tank

Dystronic · Post by **Dystronic** » Sat Jul 04, 2015 3:40 am

Thanks all, I guess it never occurred to me that the 'reserve' was just a strata of the main tank and not a separate reservoir within it. I suppose I thought there would be a 'pooling' area to inhibit centrifugal or gravitational forces drawing fuel away from the intake line. As it is, I can live with it knowing there's nothing wrong with my particular Stella. Just another unique 'feature' I'll just have to adjust to.

az_slynch · Post by **az_slynch** » Sat Jul 04, 2015 4:32 am

Dystronic wrote:Thanks all, I guess it never occurred to me that the 'reserve' was just a strata of the main tank and not a separate reservoir within it. I suppose I thought there would be a 'pooling' area to inhibit centrifugal or gravitational forces drawing fuel away from the intake line. As it is, I can live with it knowing there's nothing wrong with my particular Stella. Just another unique 'feature' I'll just have to adjust to.

The fuel reserve is a holdover from the ancient days of the Vespa, before they were fitted with fuel gauges. In those days, you simply popped open the gascap and peeked in the tank before setting off. If the bike sputtered while riding, you reached down and flipped the tap to the right, and carried on in search of a petrol station. If you had a head for figures, you could also use your odometer to help determine the fuel range.

On my '81 Vespa P200E, the cutover point is roughly 60 miles, with 15 miles left on reserve if you behaved yourself. Amusingly, this is in line with your experience of needing to switch to reserve at the 1/5 tank mark. With a Stella equipped with a working fuel gauge, you could just open the tap to reserve before setting off and rely on the gauge exclusively for monitoring fuel level. No fiddling with the tap required!

That said, scooter gauges aren't exactly known for their accuracy. A carburetor won't lie to you when it's not getting fuel. Isn't it nice to know that you have that ace in the hole, a truly reliable indicator to tell you that your fuel level is low-but-not-out and that it's time to find a petrol station rather than inadvertently overlooking the gauge and sputtering out with no fuel in sight?

srbbnd · Post by **srbbnd** » Sat Jul 04, 2015 5:06 am

I learned the hard way, even though you have fuel, if you are below 1/5 better fuel up. I have never filled up more than 1.1 gallons. I ran out of fuel right around that number as well even though there is gas, guess gravity can only do so much. Would be nice if the tank was a little bigger, or at least would use most of the fuel. Would love to be able to go a more than a week without fueling up.