FUMES !!! Very nervous

[Roidfingers]

Ive had my Valk about 5 months nw. Always in garage over night. The weather has gotten cooler and I haven't been riding. Just in the last week or two Ive noticed a very strong smell of gas fumes or maybe something like paint thinner in my garage, when the door has been closed for an hour or so. Never smelled it like this before. very strong. Question. One car garage sealed tightly. Would the vent tub on the tank create this much smell? No evidence of fuel on the ground. Ive removed 2 gas cans I had in there and also washed my shop towels.trying to eliminate the cause. Ive just had to park it outside in the rain because being nervous of the amount of smell. Any suggestions.

[CajunRider]

My guess would be a fuel line leak (fuel will drip on the top of the engine, not on the floor).  These bikes are getting some age... those rubber hoses don't last forever (usually about 10 years).  If it does turn out to be a fuel line, I would suggest changing that and all vacuum lines connected to the carbs and intakes.  Once the first one cracks or leaks, they tend to all start cracking or leaking.

Another possibility, are you over filling the tank just before getting home?  If you've been "de-smogged", then overflow will be on the floor or on top the engine instead of in the charcoal canister.  This is a smaller possibility... it's pretty easy to see the fuel overflow when it happens, and it's normally out in sunlight instead of in a garage. 

I'm sure others will chime in soon with other possibilities. 

[Roidfingers]

Just went out side. Got on my knees with a flashlight and looked over the bike. Nothing wet. No lines dripping from fuel valve nothing. could it be just the tank venting???? Looked at everything in my garage and cant find any open containers of anything. DAM

[Moonshot_1]

Ive had my Valk about 5 months nw. Always in garage over night. The weather has gotten cooler and I haven't been riding. Just in the last week or two Ive noticed a very strong smell of gas fumes or maybe something like paint thinner in my garage, when the door has been closed for an hour or so. Never smelled it like this before. very strong. Question. One car garage sealed tightly. Would the vent tub on the tank create this much smell? No evidence of fuel on the ground. Ive removed 2 gas cans I had in there and also washed my shop towels.trying to eliminate the cause. Ive just had to park it outside in the rain because being nervous of the amount of smell. Any suggestions.

Don't know how practical this would be for you but if you can get a cover so you can keep your bike outside for a few days, air out the garage and then see if the gas smell continues, I'd start there.

You might want to fire up the bike and get some fuel flowing then check the lines and petcock.

Look for "stains" on the chrome under the petcock for evidence of a gas leak. Unlike oil, gas evaporates pretty quick so looking for puddles of it as evidence of a leak will only happen with a rather significant leak. An occasional drip will still smell up the place but will evaporate quickly.

Or it is something not even related to the bike at all. Can't help much there except to remove specific items one at a time till the garage doesn't smell anymore.

[Roidfingers]

Good call Moon, kinda what im doing. I've got her outside under a tarp. Garage is closed and gonna wait and see if smell resides. Then if it doesnt. Then its bike. But haven't seen any indications of fuel. Whether running or not. Thanks for the input.

[BF]

The tanks gas cap gasket. 

[Stanley Steamer]

The tanks gas cap gasket. 

And tighten the screws holding the gas cap on.......

[Roidfingers]

BF, U may be right. I went back in to the garage. Bikes outside. Smell not near as bad. Checked the bike again with flashlight. Nothing. Sniffed around the gas cap, and smelled strong fuel. Sounds promising. Next question, where can I get one. 98 standard. Heard u can put hydraulic fluid on a gasket and it will make it expand? Also I noticed a lot of play left to right on the gas cap cover. More left when u puss down.

[Pete]

BF, U may be right. I went back in to the garage. Bikes outside. Smell not near as bad. Checked the bike again with flashlight. Nothing. Sniffed around the gas cap, and smelled strong fuel. Sounds promising. Next question, where can I get one. 98 standard. Heard u can put hydraulic fluid on a gasket and it will make it expand? Also I noticed a lot of play left to right on the gas cap cover. More left when u puss down.

I use silicone to lube and swell old rubber seals.

[Roidfingers]

As in silicone u mean. Like a spray white lithium or ?

[cookiedough]

I've had an old snowblower dripping gas out of the carb float bowl not horrible, but just enough to smell it, doesn't take much really to get an awful smell of gas in an enclosed 2 car garage.   

Air out the garage (will take a few days) with bike out and see if smell is gone.

good luck.

[PAVALKER]

A little lube or vasoline on that lid seal should take care of that for a little while.

[Sorcerer]

Check for a hydro locked motor. Pull all 6 plugs BEFORE you hit the starter button. If gas comes out the spark plug holes you have a carb that the needle seat has failed and /or a failed petcock , or both.

[Hef]

Had the exact same problem with mine. Odor, but nothing visible. Took it to the shop and they told me it was my fuel shut-off valve. Had them to replace it, problem solved. Good luck!

[Jess from VA]

Some have trimmed a (thin) gasket to just drop on top of the existing gasket (bicycle inner tube).  If you get in there to work, do not drop tiny screws down the hole, it will ruin your day.   Sometimes those magnetic tip screwdrivers really come in handy. 

Some found that a 1.5" ID Oring fit right around the round part of the bottom of the gas cap. http://www.valkyrieforum.com/bbs/index.php/topic,57951.0.html

This may not be your smell origin, but I have been surprised to read a poorly sealing cap can smell up a  whole garage a number of times on here.  People have also reported a gas smell while riding that has been the cap seal.

[Andy Cote]

Check for a hydro locked motor. Pull all 6 plugs BEFORE you hit the starter button. If gas comes out the spark plug holes you have a carb that the needle seat has failed and /or a failed petcock , or both.

REALLY NEED TO PAY ATTENTION TO THIS RECOMENDATION!

While the likelihood may be low, the results are significant and the prevention is simple.  Pull the spark plugs, spin it over and see if fuel comes out before doing anything else.

[Pete]

As in silicone u mean. Like a spray white lithium or ?

I use a spray silicone lube, sprayed on the rubber and let it soak, then spray more as needed.
Position the part where the liquid will not run off. For small parts I spray into a small container and soak the part.

Any hardware or auto store has several different brands in a spray can. Brand name seems un-important, although some stay on the part better than others

[Punisher]

The chrome tubes between your carbs and heads, check the bottom of the tubes where they bolt to the heads (if you have Kury spark plug valances those would have to be pulled) see if there is any brownish residue around them.    If so that is the o-rings under them leaking which can cause a gassy smell.   Also check the clamps on the rubber connectors between those tubes and the carbs, make sure they are tight.

I've also experienced this issue when filling up the tank extra full at a station near the house and then parking it, especially in warm/hot weather.   By "packing" the tank when it is hot and the tank is expanded from being hot, once placing it indoors and the tank cools off (shrinks) some drops of fuel can be pushed out the overflow tube which will evaporate pretty quickly on the floor but leave a lingering gas smell for quite a while.

[Firefighter]

I have three bikes and gas cans, all kinds of oils, cleaning rags, tools, and many other things in my single car garage. If I leave it closed for a couple of days it smells of motorcycles especially if I had rode in the last day or two. I don't smell raw gas just a combination of oil, exhaust, tires, etc. I never thought any thing wrong, just a closed garage. If I leave a window cracked open I smell nothing. None of my bikes are leaking anything.

[art]

When checking for hydrolock do it outside. If there is gas in the cylinder and you turn over the engine by hitting the starter gas will go out like a fire hose . I've seen it shoot about 10 -15 feet. Best to turn it over by putting in gear and rolling the bike.

[Moonshot_1]

Thinking the culprit is the cooler weather. I'm liking the gas cap gasket as suspect #1. The cooler weather might have had an effect on the gasket, basically making shrink some in the cooler weather.

I do believe that if hydrolock was the issue we wouldn't be discussing a gas smell but why the bike went "CLANG" when you tried to start it and to figure out why it is no longer able to start. I do believe you have had it running very recently as you said there was no leaks when running.

I have a 99 I/S and am currently tracking down some fuel smells as well. Having the air filter and intake o-rings replaced. Tried the o-ring trick with the gas cap and didn't notice any significant improvement.

But for you, I'm liking the gas cap gasket as the suspect.

[DavRed]

The tanks gas cap gasket. 

Replaced my gas cap for the same reason. Problem solved....

[RP#62]

I had that happen once.  Turned out to be the petcock going bad.  The diaphragm had begun to seep and fumes were coming out of the weep hole in the bottom of the petcock.

-RP