2006 Buddy 50 fills garage with gasoline vapor smell

[MohnJadden]

I bought an '06 Buddy a month or so ago and have been riding it whenever the weather permits for relatively short distances in and around town. After riding it to/from the train station on Thursday, I parked it in my garage Friday as I normally do, then left it there since it rained all day.

Friday night I went to toss out some recycling and there was a pervasive, sharp odor of gasoline vapors in the garage. I opened the garage door to ventilate it, then checked my lawn mower, Buddy, and plastic gas jerry can for any leaks. No leaks, and fuel levels in each were commensurate with where they ought to be.

After an hour, I closed the garage door, then went out again to smell-test. Again, gas vapor. I ventilated it again, closed it after a half-hour, and went to bed. Today, the smell was still there in the morning.

I rode my Buddy without issues for around 30-45 minutes this AM after having ventilated the garage door. I came back and there was no smell, and after an hour or two, the smell is back.

Something, somewhere in my Buddy is letting gas vapors out. I'm concerned that a stray spark could turn my garage into a fuel-air-explosive bomb. I plan on keeping the scooter parked outside overnight (I'm on a crescent cul-de-sac, and it'll be chained to something solid) but does anyone have any ideas on what I should do to diagnose the issue or fix it? I'm not exactly Mr. Auto Mechanic but I have a socket set and plenty of work gloves, and worst case scenario I can ride it to the motorcycle repair guy next town over.

[az_slynch]

I bought an '06 Buddy a month or so ago and have been riding it whenever the weather permits for relatively short distances in and around town. After riding it to/from the train station on Thursday, I parked it in my garage Friday as I normally do, then left it there since it rained all day.

Friday night I went to toss out some recycling and there was a pervasive, sharp odor of gasoline vapors in the garage. I opened the garage door to ventilate it, then checked my lawn mower, Buddy, and plastic gas jerry can for any leaks. No leaks, and fuel levels in each were commensurate with where they ought to be.

After an hour, I closed the garage door, then went out again to smell-test. Again, gas vapor. I ventilated it again, closed it after a half-hour, and went to bed. Today, the smell was still there in the morning.

I rode my Buddy without issues for around 30-45 minutes this AM after having ventilated the garage door. I came back and there was no smell, and after an hour or two, the smell is back.

Something, somewhere in my Buddy is letting gas vapors out. I'm concerned that a stray spark could turn my garage into a fuel-air-explosive bomb. I plan on keeping the scooter parked outside overnight (I'm on a crescent cul-de-sac, and it'll be chained to something solid) but does anyone have any ideas on what I should do to diagnose the issue or fix it? I'm not exactly Mr. Auto Mechanic but I have a socket set and plenty of work gloves, and worst case scenario I can ride it to the motorcycle repair guy next town over.

Had you filled the tank recently? Maybe the seal on the gas cap tore or fell of the cap. The seal for the fuel gauge could crack and vent too, but it isn't subjected to the frequent torisional forces experienced by the gas cap seal when the cap is removed and installed.

If those are in good shape, maybe the vacuum diaphragm on your fuel tap failed and is leaking a small amount of fuel into the intake which is evaporating.

P.S. I may be wrong, but the Buddy 50 may not have an evap cannister. I cant remember seeing one on the last one I worked on.

[k1dude]

Never top off the tank of a Buddy. It's a common mistake that new owners make.

Keep the fuel level at least an inch below the top of the tank (the actual tank, not the cap port).

[BMW_Art]

And if you have one, a carbon canister can also cause a fuel smell. Particularly if the tank was filled to max. That often causes a hard start so is less likely but checking it and connecting hoses isn't a bad idea.

Also if bought used the original owner might have made some modifications like removing the PCV valve or roughing a return line to a PCV valve. I can't say for certain but many of the pergormance threads I e been reading discuss such options.

[MohnJadden]

Had you filled the tank recently? Maybe the seal on the gas cap tore or fell of the cap. The seal for the fuel gauge could crack and vent too, but it isn't subjected to the frequent torisional forces experienced by the gas cap seal when the cap is removed and installed.

If those are in good shape, maybe the vacuum diaphragm on your fuel tap failed and is leaking a small amount of fuel into the intake which is evaporating.

P.S. I may be wrong, but the Buddy 50 may not have an evap cannister. I cant remember seeing one on the last one I worked on.

The seal looks intact as far as I can tell, and there's a slight amount of pushback when I tighten the gas cap, so it feels like it's present. I did notice that one half of the inner part of the gas cap was a bit moist, and the scooter was sitting idle for hours when I unscrewed it.

Is there an easy way for me to diagnose the vacuum diaphragm or at that point are we talking professional repair?

Never top off the tank of a Buddy. It's a common mistake that new owners make.

Keep the fuel level at least an inch below the top of the tank (the actual tank, not the cap port).

I filled the tank last week, fairly close to the top, so I'll err on the side of leaving a few inches going forward. Thanks for the pointer!

And if you have one, a carbon canister can also cause a fuel smell. Particularly if the tank was filled to max. That often causes a hard start so is less likely but checking it and connecting hoses isn't a bad idea.

Also if bought used the original owner might have made some modifications like removing the PCV valve or roughing a return line to a PCV valve. I can't say for certain but many of the pergormance threads I e been reading discuss such options.

No hard starts. The original owner said he didn't make any modifications to the scooter.

[az_slynch]

The seal looks intact as far as I can tell, and there's a slight amount of pushback when I tighten the gas cap, so it feels like it's present. I did notice that one half of the inner part of the gas cap was a bit moist, and the scooter was sitting idle for hours when I unscrewed it.

Is there an easy way for me to diagnose the vacuum diaphragm or at that point are we talking professional repair?

If you look under the tail of the scooter, you should see a cylindrical assembly with two hoses poking out of it, heading to the engine. Might be easier to find with the seat bucket removed. The lower and smaller of the two hoses from that assembly is the vacuum line that opens the fuel tap when the engine is cranking over/running. Remove the line from either the fuel tap or the intake; the inside of the line should be dry. If it's got fuel in it, you probably need a new fuel tap. Easy part to change out, thankfully.

Still thinking your fuel cap is the culprit, though.

[Dooglas]

Remove the line from either the fuel tap or the intake; the inside of the line should be dry. If it's got fuel in it, you probably need a new fuel tap.

Yes, definitely one thing to check. Another are the fuel lines themselves. They tend to deteriorate as they get old (we are talking about an 11 year old scooter here) and you may have a crack someplace. Also, inspect the fuel cap carefully. Not only could the gasket be bad, but a previous owner might have attempted to add a DIY enlarged vent in the cap. That could cause a small fuel leak as you ride.

[MohnJadden]

Should I be doing this on a fully dry tank?

[az_slynch]

Should I be doing this on a fully dry tank?

You can check the vacuum line without emptying the tank. All that line should move is engine vacuum pressure when running.

[MohnJadden]

I rode it around at full throttle for a few commutes and that seems to have done the trick - my garage no longer smells like a match will set it alight. Note to self, keep the tank at around above 3/4ths full to be safe.

Thanks for the help and support, all!