The assumption re:Hydrolock and a good petcock.

[Ricky-D]

The assumption there is enough volume of gasoline remaining in the gas line to be able to cause a hydrolock situation is exactly that. An assumption.
There has been not one post regarding a factual methodical attempt to determine what the truth of the matter is. Just a lot of conjecture and assumption.

Besides that question,,, has anyone considered that the carburetor is not filled to the brim, filled to a point where any little bit of gas will overflow into the cylinder. Of course not, it isn’t like that at all.
It is going to take a certain amount of gasoline to fill the carburetor up to a point where it will start flowing into the cylinder.

So, if the gasoline that is in the gas line was allowed to leak into the carburetor,,, just exactly how much of that will be used to fill up the carburetor to a point to which it will then start leaking into the cylinder. This has never been considered.

And do you think the gasoline will be able to flow willy nilly, emptying the fuel line, (if allowed to), because of a faulty float Needle/valve? I don’t think so. The fuel will stay right there in the line as it is because there is no air going to be allowed to get into the line to let the fuel flow out.

So now, there still remain some who would say "you can still get a hydrolock", with a petcock that has been shut off, and does not allow any gasoline to flow.  How can that be? It must be magic because the answer certainly doesn’t reside in fact. The truth be known, they still have a faulty fuel petcock.

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[Chrisj CMA]

The best protection from hydrolock is a properly working OE petcock. Of course the problem is with that OE Piece the way you know it is going to malfunction is when it’s not. Some people (like me) find out that petcock isn’t working right when the engine won’t stay running because not enough fuel is flowing. The unlucky people find out it’s not working when they get a hydrolock. With a Pingel turned off when not riding you lose the risk of wondering if that OE valve is still operating properly.

[indybobm]

Let me make one assumption: that anytime a Pingle valve is turned on, it will flow fuel.

This should not be difficult to test with the carbs off of the bike and the fuel line from the petcock.
Cut the tip off of one float valve and with the carbs on the bench in the normal position and the gas tank positioned in the correct position, turn on the Pringel and see what happens.

If you turn off the engine and are a little slow in turning off the Pingel, how much gas will flow in the above situation? All it takes is gravity for the gas to flow if it has somewhere to go.

[98valk]

the OEM valve turns on/off also just like a pingel. so if people don't be lazy and shut it off, then no hydro lock. simple as that.

[Pete]

the OEM valve turns on/off also just like a pingel. so if people don't be lazy and shut it off, then no hydro lock. simple as that.

It is a little more complicated than that, because the shutoff valve can malfunction from dirt/rust contamination. If the shutoff valve is compromised before the diaphram you will not know it because the  diaphram stops the flow.

I have seen it happen from a rusty tank. Rust in the tank can compromise both and cause the problem with little to no warming.

[98valk]

the OEM valve turns on/off also just like a pingel. so if people don't be lazy and shut it off, then no hydro lock. simple as that.

It is a little more complicated than that, because the shutoff valve can malfunction from dirt/rust contamination. If the shutoff valve is compromised before the diaphram you will not know it because the  diaphram stops the flow.

I have seen it happen from a rusty tank. Rust in the tank can compromise both and cause the problem with little to no warming.

and a pingel can be compromised from a dirty/rusty tank also. this is why the fuel filter sock should be in place.  any valve, some types more than others can fail for various reasons.
still bottom line shut the valve off.

[RWhitehouse]

A stuck needle will absolutely empty the fuel line.  I have personally seen and observed this happening. Not speculation or assumptions.

What it doesn't do is fill up the cylinder. It dumps out of the carb overflow hose, exactly as it was intended to. These vent/overflow ports are chained together just like the fuel supply lines are. So you could tell which bank has the leaky carb, but not which one at first glance. The float needle controls flow of fuel to the BOWL, not to the ENGINE. Not the same thing.

Now, some of this does seep past the jet needle even at idle when it is fully down. Enough to make that cylinder run very noticeably too rich and smoke out the exhaust. The quantity of fuel in the line would not be sufficient to cause a hydrolock. 95% of it would end up on the ground out the overflow. A couple mL's might seep past the jet needle or through the idle circuit and end up in the cylinder.  If every drop of fuel in the line ended up directly in the cylinder, then yes, it's probably enough to hydrolock. But that is not going to happen- assuming the vent is not plugged or obstructed, but if it was, that cylinder wouldn't run. The carb bowl has to vent to atmosphere. If it couldn't, it could create negative pressure once the engine starts  and no fuel would get pulled through the jets.

Now, if say you had a faulty needle/seat and left the tank petcock on. Or had a faulty OEM one that wasn't closing. Again, most of the fuel would overfill the bowl and come out of the bowl overflow/vent causing a simple fuel leak onto the ground.  Given enough time and fuel to leak through (i.e, an entire tank, not a couple OZs in the fuel line), the small amount that seeps past the jet needle/pilot circuit could feasibly flood the cylinder.

So yes, I agree that "you can still hydrolock even with petcock off" is unrealistic. Assuming it truly is OFF, and not leaking or otherwise faulty.

[semo97]

Are most hydrolocks on the left side or right side cylinders? If it is the left could it be because it is leaning to the left on the side stand. Gas will go the direction of least resistance and if the carb overflow is above the leak it will go to the cylinder. You will also have the right carb bank above all this and if there is a problem on the right side it may flow out the overflow easier. Just a thought may be way out in left field on this.