Leaky right carb, fuel in crankcase?

[AndrewB]

I have a 83 R65 w/ 45k miles. Two days ago when parking in the garage I forgot to turn off the petcock.  This morning there was a small pool of gas, about 6" in diameter on the floor under the right carb. I checked the tank and I still have some gas in there, eye balling it I'm close to where I should be w/ the miles on the trip meter.

Gas is shutting off when I bring the floats up to level.

Would this mean it's definitely bad floats?

How can I tell if gas has gone into the crankcase? Should I worry about this?

I had both carbs apart earlier this week checking to make sure the idle circuits, etc,  were clear. My idle has been fluctuating aprox. 50-100 rpms at stop.

[Rob Valdez 79 R65]

Have you tried starting it, yet?  If not, I would wait until you have checked it out, first, just in case you have a head filled with fuel.  

Was the bike on the center stand?

Have you checked the oil level on the dipstick?  Does it look to be the same consistency as normal?

I suppose sinking floats could make your idle fluctuate.  They would definitely account for overflow of gas.
The best way to check for bad floats is to weigh them, and compare the weight to a new one.
If you haven't replaced them since you got the bike, and they are particularly nasty dark yellow, I would say go ahead and spend the money on a new set.  They are a long-term consumable.  And that long-term seems to be getting shorter with today's current fuel.

[AndrewB]

Haven't tried starting it. It's on the center stand, haven't moved it. The floats are a nasty yellow/brown, time to replace them.

Checked the oil, changed it a couple hundred miles ago. It's at the same level it was last time I checked it, between the two lines. It seems to be a similar consistency to new oil, maybe slightly thinner. I couldn't smell any gas in the crankcase

[Barry]

With luck the fuel on the floor came from the carb overflow.  

Sounds like you are OK. I would remove the plugs and take a peak into the cylinders to make sure.

[montmil]

Besides the floats, I would check the float needle and its seat. The smallest bit of grit or crud -perhaps deteriorating fuel line- can prevent the needle from closing off fuel supply.

Pull the spark plugs and securely ground them to the cylinders -well away from the plug holes- then crank the engine to see if any fuel blows from the plug hole.

If you have any concerns about oil in the crankcase, consider the price of an oil change vs bearing damage. I'd change the oil just to be sure.

Monte

[Julio A.]

I had leaking carbs before; the culprit was the pin where the float pivots; The pin got rusty and would occasionally stick on the either fully closed or fully opened position.  

btw, How can the fuel enter the crankcase?

[Barry]

btw, How can the fuel enter the crankcase?  

Only by getting past the rings which it will do given time.

[benlawlor85]

i had a leaking carb years ago, changed float etc etc and it turned out that the actually bowl had a small hole in it next to the over-flow tube. worth checking.

[AndrewB]

Grounded the spark plug on the head, cranked it over a few times and no gas came out. Had the fire extinguisher ready just in case:)

I'm going to change the oil just to be safe.

I checked the bowl, no cracks or leaks. I turned on the petcock, held the floats at the exact shut off point for sometime, no drip. Fuel line and filters are less than two years old.  

Time to order new floats, float needles, etc. I thinks.

[Rob Valdez 79 R65]

And the standard floats will be just fine, as opposed to the alcohol proof ones.  
If I understand it correctly, the alcohol-proof ones are the ones that can pivot independently of each other?

I wonder why they don't make metal floats, like are in so many of the Japanese bikes?

[donbmw]

You can get the alcohol proof floats made like the stock floats now. I have had them for a couple years.

Don

[Bob_Roller]

The Bing part number for the alcohol resistant floats is 35-310, about $37US each, only available from Bing .

These are not the independent floats that requires you to replace the carb bowl .