Gasoline vanishing

[Flyinfool]

Go back to post 3.

Mine did that about 4 years ago and never a repeat performance.

 

Bike locked in shed.

Gas tank locked.

The only keys are in my pocket.

No sign of gas in oil.

No sign of gas dripping on ground.

No kids still at home.

Just a half tank gone.

Never did find a plausible reason for it.

 

On a 1st gen the top of the tank is well above the carbs. It is possible for gas to gravity feed from the tank to the carbs until the level of gas in the tank gets down to the level of gas in the float bowls. The pump has 2 one way valves that will allow gas to flow from the tank to the carbs but not allow gas to flow from the carbs to the tank. So it is possible for gas to drain from the tank to the carbs for about 1/3 of the tank.

 

The best WAG that I came up with was that it was stored with a full tank, there was a small piece of dirt on the float needle seat allowing the slow leak, first time I ran it the dirt washed out never to return.

 

 

Even though you have been riding it all week, I would still give the oil a good check for gas contamination, no sense doing any additional damage to the bearings.

[cabreco]

Even though you have been riding it all week, I would still give the oil a good check for gas contamination, no sense doing any additional damage to the bearings.

 

She's due for an oil change anyway so I will check it out!

[flyday58]

Following up on Jeff's thoughts, if dirt and an open float needle were the culprit, I guess it would also be possible for a syphon effect to occur, like syphoning gas from a tank or water from a pool. Once it's going it might continue. But I'd still be looking for a strong gas odor in that case. Just reaching here...

[cabreco]

Now I ask because I have no clue but, wouldn't the above scenario, be accompanied by a strong gasoline odor in a closed attached garage?

[Flyinfool]

Maybe.

 

If the overflow of the bowls was going out the overflow onto the floor, then yes. If the gas is going into the engine, then no.

 

If the garage has good ventilation like it should, you also may not notice the gas smell.

 

When my half tank disappeared, there was no smell.

[cabreco]

Well the bike has been sitting since the last posted fill up...as of today I STILL have a full tank of gas. I HATE THE GREMLIN!

 

[Flyinfool]

Sure sounds like the same gas drinking gremlin that I had. I am glad he found a home other than at my house......