Gas Problem

[Louis McGinty]

A couple of days ago, I go out and find gas all under my bike which is a 98 Standard.  Location of the gas flow is from one of two hoses that end at the chrome rail that go across at the back of the two carb rails, the hose goes to each side of the carb rails and T's off between the back two carbs on each side.  This happens only when the gas is left on.  I had heard when the petcock fails gas can fill the cyclinders and cause a serious problem, have no gas in cyclinders and bike will crank and run fine.  Am I right in that the petcock needs to be rebuilt or replaced.  I hope some of you can make sense out of the description that I gave about where the gas was coming from.  Any help is appreciated.

Louis

[Daniel Meyer]

You have two issues.

Petcock needs rebuilt for sure. It should stop gas flow with the engine off.

You also have a carb float valve stuck/crudded up. Those hoses are the carb bowl vents and for gas to come out of them a carb must be overfilling. Sometimes (especially if the overflow is on the left/downhill while parked carb bank), that gas could enter the cylinder as well, causing the dreaded hydrolock.

[Minnie Miles]

I am having the same problem and it is the 10% ethanol

[fstsix]

As posted above, the petcock should be checked. If and when you take it apart you will see the diaphragm, if it is split or cracked it will transfer the fuel to the (vacuum) side chamber witch intern will get sucked into the vacuum side of the Carb. When parked with gas in the (On) position it could be seeping into the carb vacuum port and down the intake runner to fill the cylinder usually the side it is leaning to on the kick stand.

[Hoser]

I am having the same problem and it is the 10% ethanol

How's that? As far as I know unleaded gas will flow thru a bad petcock also.  ??? hoser

[Minnie Miles]

I am having the same problem and it is the 10% ethanol

How's that? As far as I know unleaded gas will flow thru a bad petcock also.  ??? hoser

The petcock was fine untill the 10% ethanol hit it last month, when the entire USA changed to 10%.

[fstsix]

In the old days we always new that Alcohol fuel required mods on the Carbs, do to the fact it would dry out rubber O rings gaskets ect, one  would think ethanol could have adverse effects also it probably does, and these Old girls are getting older sure doesn't help read this.http://www.rodandcustommagazine.com/techarticles/0812rc_aftermarket_carburetors_ethanol_fuel/index.html

[Hoser]

well jeez, we still have plenty of unleaded here in corn country, I usually get whatever is cheapest.  I've not had any problems with either, and I've had my Valk for nine years.  Maybe I'm just lucky!  Hoser