Bonneville America Forums Forums Technical Forums General Tech Fuel in My Air Filter?

Is it "normal" to have a small amount of fuel in the airbox/air filter?

I was giving my bike the once over after having it sit for about 8 weeks (changing plugs, checking air filter, etc.), including turning it over and warming it up in the garage, etc. I didn't actually ride it and only had it running for 5-6 minutes.

Anyway, I noticed a strong gasoline smell from the air box, and when pulled out my K&N air filter, I saw a small amount of fuel on the bottom and a little more pooled in the corner of the airbox. (Less than 1/4 of a teaspoon).

Any thoughts on if I should worry or if this indicates a set-up problem with my air/fuel mixture? (Maybe I just revved the cold engine too hard?)

My airbox had about a half a cup in the forward part of the airbox (forward of the 2 holes in front of the filter element). Investigating a strong smell of gas, I took things apart until I saw the gas. Cut a small hole at the base of the wall below the 2 holes near the bottom so any gas buildup in the future would go down the airbox drain. In my case, I think a float was sticking at some point (it was running very rich and would die at a stop) and managed to have gas flowback into the box. At least that's the only way I could figure it got there. After the running problem resolved itself, there were no more gas in airbox probs.
The reason you have gas in the airbox may be different but whatever the reason, I don't think it's normal.

That is also a sure way to splode your airbox first time it backfires. Not a good thing. Drain the stuff from the big hoses on the bottom of the airbox, remove the little squirrel condoms and crud should pour out.
You should check your floats too, and the little secret T filter. A search will show the location of these items.
If it's still warrantied, take it to a dealer ASAP

I just removed my airbox and found what looked and felt more like old dirty oil.
Could there be a blow-by problem and this stuff came through the breather hose, since it looked like oil?

A bit of oil collected in the airbox is normal. That's why part of the 6K mile service is to open the drain hoses. Running the bike as fast as it likes to go tends to fill the crankcase with a fine oil mist that gets carried out the breather hose and condenses in the airbox. When the engine wears enough to have any serious amount of blow-by, the sparkplugs will start collecting shiny, wet looking carbon deposits.

As for gas collecting in the airbox, by any chance was the bike parked with the petcock left on? A lot of the Hinkley bikes are equipped with a polution control valve that closes the floatbowl vents when the ignition is off. (cycle the kill switch with the engine not running. If you hear a sound like a relay clicking, you have this) When it's even slightly warm, the gas in the floatbowls will expand. With the vents closed, it has noplace to go but up the main and pilot jets into the carb bore. Some will evaporate there, cooling the carb and the gas in the bowls contracts, the float drops, the bowls refill and it starts all over again.

Hmmm... interesting explanation. Something I definitely did not know, but will look into.

Side note for Pat: I had the bike out late last night for about 90-100 miles (about 40F degrees out.. brrrrrrr), and she didn't "splode"... so I'm happy. Now if I could just thaw out my fingers.

Glad ya didn't splode.

i have same problem and have heard the clicking from the relay ,my bike has been sitting for a while and i have had the battery on and off, if i start it up will this correct itsself, as i have fuel seaping out of left carb