Fuel in my air cleaner box?

[bluegoatwoods]

The bike in question is a recent Icebear 150 cc GY6.

She's certainly showing evidence of flooding. Often no-start. Or running rough and idling poorly when it does start. So yesterday I was cranking her and I could see fuel coming out of the overflow tube. Okay.

Then today I noticed a drip from my air filter box. Opened it up and the filter is absolutely wet with gasoline. When cranking, also, the fuel flow into the airbox increases.

So I'm thinking that the carburetor float and the shut-off valve in there ought to be inspected. And I'll do that. Perhaps tomorrow.

But I'm also putting this up in case I've missed anything. Anyone have any other notions of just what I should look at or look for?

[90GTVert]

The float would be my first check. Check the height and also make sure there's no debris in there. I'm not a fan of vacuum petcocks and always swap them out with manual shutoffs. They don't fail very often. The biggest problem with them is the user that may or may not turn them off.

[bluegoatwoods]

Thanks, Brent. The float is obviously the prime suspect.

One thing I forgot to mention. This is the type of scooter where the gas tank is below the floorboard. The 'petcock' looks like the same type of thing that's found on a scooter with a rear-mounted gas tank. But it's a bit bigger. It also needs to pump fuel uphill. I'm at a loss as to just how it does that.

But this is not likely to affect my issue, is it?

[90GTVert]

No, it's obviously able to move the fuel.

wiki.bssd.org/index.php/Diaphragm_Fuel_Pumps

[bluegoatwoods]

Well, I swapped my carburetor for a spare I've got sitting around and now my bike is running very nicely.

I cleaned the outside of the old carb with carb cleaner and not it's sitting in front of me in a Zip-loc bag.Now I get to tear a carburetor apart and become familiar with all of those small parts.

I might not start on it this evening. But I'll get to it sometime soon. It'll be valuable experience.

[bluegoatwoods]

Okay....so I started on the carb cleaning today. Since it's my intent to photo these small parts along the way, in order that I can figure out how to put them back together again, I also might as well show my steps right here.

You veterans who read this can help me out if I make any mis-steps. Plus this might be helpful to any newbies who haven't done it yet.

I purposely got some blue shop paper towels for this job. I'm thinking that they're less likely to get fibers on the inside of my carburetor.








So this brought me to a screeching halt. I might have continued to the float bowl. That's where I suspect that the actual problem lies anyway. But I had other things that needed doing today anyway and I might as well resume this project when I've got the things I need on hand. I do have a spring loaded punch and extractor set, by the way. So I ought to be ready to go once I get a small supply of new fasteners.

[FrankenMech]

If you have a battery operated impact driver try it on phillips head screws. The impact action keeps the driver from caming out and stripping the head.

A dremel tool with a cutting disk can be used to slot the head on a screw.

[bluegoatwoods]

Jul 20, 2017 19:32:26 GMT -5 FrankenMech said:

If you have a battery operated impact driver try it on phillips head screws. The impact action keeps the driver from caming out and stripping the head.

A dremel tool with a cutting disk can be used to slot the head on a screw.

Good ideas! Thanks.

[bluegoatwoods]

Welll......not a lot, really, to report on this project. I'm feeling a bit sheepish over ignoring a project that I'd really like to do. But life is busy. So, with that pathetic excuse.......

I looked at a disrupted work schedule over the last few weeks and decided to put this project on the back burner.
I simply bought a new carburetor. They're only about $22, after all.

So it arrived last week and I installed it on the bike. She started right up and I took it out for a test spin.
Seemed fine. Then I took it out on another errand...and.....she started flooding again!!

Recall that this is the type of bike where the gas tank sits under the floor-board. So I have no trouble with fuel leaking out while the bike is sitting. Only when running.

In either case, though, I can't help thinking that the only cause of this must be the float/needle valve. Am I right on that? Is there some other reason for constant flooding?

The other day I took the bowl off of that new carburetor and checked the float/needle valve. All seemed okay.
So I put it back together and took the bike out for a test drive. Everything was fine for a couple of miles until it started flooding again.

So today I took it apart again and tried to bend the hanger just a bit. I'm not even sure I changed the angle at all. But I was being careful since I'm new to this sort of stuff.

I guess I'm not too worried. Sooner or later I'll get that needle valve working properly.

[90GTVert]

If the float height change fixes it, then I guess you know your problem. 2 carbs doing it does make me suspicious that the float isn't the issue. Too much pressure from a fuel pump could be more than the carb's float setup can handle, but I really don't know what these vacuum pumps are capable of. Could be that these carbs are intended for gravity feed and the pump is just a bit much for them so the float needs to be set differently.

[bluegoatwoods]

Aug 9, 2017 6:48:43 GMT -5 90GTVert said:

If the float height change fixes it, then I guess you know your problem. 2 carbs doing it does make me suspicious that the float isn't the issue. Too much pressure from a fuel pump could be more than the carb's float setup can handle, but I really don't know what these vacuum pumps are capable of. Could be that these carbs are intended for gravity feed and the pump is just a bit much for them so the float needs to be set differently.

As a matter of fact I had been wondering about that fuel pump, too. But I had discounted it on the grounds that if the pump were pushing too much fuel that shouldn't have any effect on the needle valve. 

But if it were pushing too hard, then maybe. But I wonder if I can even figure out a way to confirm it.

I rode the bike several miles yesterday with no flooding. So it looks hopeful. Right now I have a dilemna on my hands; going to work I ought to ride the bicycle for the sake of exercise. But I also ought to ride my scoot. For the sake of testing it.

I'll have to leave soon and I still haven't made up my mind.

[bluegoatwoods]

I think I'll ride the scooter. Even if it starts flooding on the way to work I now know that all I need to do is reach down there with a stubby screwdriver and drain out the excess. I think the bike will start back up then. Unless there's something else wrong. I probably won't even be late.

I'm lucky enough that I don't actually need to rely on my scooter for any and all transportation. And it actually could wait until I have a bit more free time.

Yet I'm feeling kinda obsessed with knowing, not just guessing, whether or not it's fixed.

[jackrides]

How far above the carb is the bottom of the gas tank? A fuel pump may not be needed.
I've had excellent success removing tough screws with a hand held hammer driven impact driver. A 6 oz to 12 oz hammer is all that's needed. The inward force of the hammer breaks loose (hopefully) any corrosion while at the same time the rotating action begins the removal. The screwdriver tip must be a snug fit in the screw head.

[bluegoatwoods]

Aug 9, 2017 11:34:12 GMT -5 jackrides said:

How far above the carb is the bottom of the gas tank? A fuel pump may not be needed.
I've had excellent success removing tough screws with a hand held hammer driven impact driver. A 6 oz to 12 oz hammer is all that's needed. The inward force of the hammer breaks loose (hopefully) any corrosion while at the same time the rotating action begins the removal. The screwdriver tip must be a snug fit in the screw head.

Thanks.

My tank actually sits below the carb.  Below the crankcase, for that matter. It's one of those types where the gas tank is below the floorboard. And I'll surely get an impact driver if needed. But it might not be needed since I have an extractor set. I just need to find time to use it.

But I've ridden the bike somewhere around 15 miles in the last day and there's no sign of flooding.  The last few go-arounds have brought flooding within a couple of miles. Maybe only one. So increasing the tension on that needle valve seems to have gotten me somewhere. 

[lostforawhile]

if it has a fuel pump, it's somehow running too much pressure and overwhelming the needle valve. verify it's a pump, it would have to be for fuel to flow upwards to the carb