hydrolock question

[turtle254]

When the float bowl overflows, how does it get down the inlet. Shouldn't  go out the overflow vent on top of the engine. For some reason when I trailer the bike and forgot to turn the fuel off, 4 cylinders filled with gas. This is not from the petcock, but I guess bounce on the rough roads causes floats to overflow.
Just don't see a path to the cylinders and not the overflow vent lines?   

[Ramie]

If your float valves leaks it goes right into the engine.

[Jims99]

The vacuum side of your petcock is not working properly. That will cause fuel to enter the carbs when bike is not running. When trailering, the bouncing around will cause the floats to bounce and pass fuel and overflow. (Petcock rebuild) The extra fuel will make its way down the carbs and into the top of the cylinders witch will cause hydro lock. Even if the float needles are working right, that much gas will not get into the cylinders if the petcock is working properly.

[MarkT]

I got fed up with the repeating failures of the OEM petcock and replaced it with a manual Pingel.  And installed a Dan-Marc fuel solenoid on both road bikes - no Dan-Marc on the blown bobber George; has a completely different fuel system - but does have a Pingel.  Put a Dan-Marc on my Honda garden tractor too!  Now I've worn it out and replaced it with a Kubota.

[turtle254]

The vacuum side of your petcock is not working properly. That will cause fuel to enter the carbs when bike is not running. When trailering, the bouncing around will cause the floats to bounce and pass fuel and overflow. (Petcock rebuild) The extra fuel will make its way down the carbs and into the top of the cylinders witch will cause hydro lock. Even if the float needles are working right, that much gas will not get into the cylinders if the petcock is working properly.

Thats wrong, My petcock is ok(check that). The amount of fuel in the float bowl did lock the engine up. My question was the path to the cylinder and not going out the vent on the bowl which I though it was supposed to do?

[DeathWishBikerDude]

I don't know how it gets there..but when I freed my engine up by slowly bumping the starter..a gallon of fuel ran out the exhaust pipes...

[Speedy Coop]

If the float bowl over fills, the gas will usually run up through the main jet then into the intake runner. Very few carbs have overfill protection. The vent hoses allow air in so the motor will not starve for fuel.

[Timbo1]

Thats wrong, My petcock is ok(check that). The amount of fuel in the float bowl did lock the engine up. My question was the path to the cylinder and not going out the vent on the bowl which I though it was supposed to do?

My understand is there are two places that must fail in order for a hydrolock condition to occur.  The first  is petcock allowing fuel to flow when there is no vacuum and two the float needle valve seeping fuel.  Bouncing floats when hauling could cause the float valve to open on rough roads but that doesn't explain why your petcock allowed fuel to flow to 4 cylinders when there was no vacuum.  Indicating your petcock is failing.  I'd suggest you do a vacuum check on your petcock and make sure no fuel seeps when there is no vacuum applied.

The vent lines which connect to the upper fuel / air rails are higher than the main jet so once your bowl is over filled with fuel and neither your petcock nor the float valves stop fuel flow it goes straight up your main and down the intake into the cylinder.

[MarkT]

Thats wrong, My petcock is ok(check that). The amount of fuel in the float bowl did lock the engine up. My question was the path to the cylinder and not going out the vent on the bowl which I though it was supposed to do?

Your petcock is NOT ok.  It's passing fuel when it shouldn't, and pushing that fuel on through past the failed float valve, high water line of the carb bowl level.  An electric fuel shutoff solenoid is insurance when your petcock fails as yours has.  As for me, as I said I eliminated both the POS Honda petcock and added the insurance.  I don't have any hydrolock worries. Don't believe my experienced response; it's your money.

[turtle254]

Thats wrong, My petcock is ok(check that). The amount of fuel in the float bowl did lock the engine up. My question was the path to the cylinder and not going out the vent on the bowl which I though it was supposed to do?

My understand is there are two places that must fail in order for a hydrolock condition to occur.  The first  is petcock allowing fuel to flow when there is no vacuum and two the float needle valve seeping fuel.  Bouncing floats when hauling could cause the float valve to open on rough roads but that doesn't explain why your petcock allowed fuel to flow to 4 cylinders when there was no vacuum.  Indicating your petcock is failing.  I'd suggest you do a vacuum check on your petcock and make sure no fuel seeps when there is no vacuum applied.

The vent lines which connect to the upper fuel / air rails are higher than the main jet so once your bowl is over filled with fuel and neither your petcock nor the float valves stop fuel flow it goes straight up your main and down the intake into the cylinder.

Like I said my petcock works ... check and double checked. Looks like there is more than enough gas to lock it up, because the petcock with no vac. will not flow and with vac. does. The roads I took were rough as could be . Thanks for the info on height of vent conn. I though it was for overflow not just a vent.

[98valk]

When the float bowl overflows, how does it get down the inlet. Shouldn't  go out the overflow vent on top of the engine. For some reason when I trailer the bike and forgot to turn the fuel off, 4 cylinders filled with gas. This is not from the petcock, but I guess bounce on the rough roads causes floats to overflow.
Just don't see a path to the cylinders and not the overflow vent lines?   

if your bowl vent lines are not sloped correctly they will create a trap, which allows the fuel to raise up to the carb throat and then down into the cylinder. if the valves are open then the cylinder gets filled.

I org posted this in '08

Re: Another hydrolock question

Posted By: 98valk <fitness7days@nospam.juno.com>
Date: 9/4/2008 at 12:30:31

In Response To: Another hydrolock question (G-Man (Gary in NY))

this is from Rider mag sept 1988 about the '88 goldwing Gl1500.
they had the hydro-lock problem and it turned out to be the bowl vent hose was sagging. "the low spot fills with gas and prevents air circulation, much like a sink trap. without a connection to atmosphere, the float bowls pressurize and raw fuel is forced up and out of the carbs through the needle jet. From there gravity takes the fuel down the intake runners. if that cylinder has an open intake valve, hydrolock."
The article states that honda issued a Product Update kit on a fix in feb of that yr which included a metal air-vent pipe and a vacuum fuel valve."
Looking at the Valkyrie service manual pics in the carb section it shows the vent hoses as straight sections just laying loosely on top of other hoses. My 98's vent hoses have a 90 degree end. the end is installed into holes in the rear carb support frame.
So this might be the reason and cause of the problem for some bikes.

http://www.valkyrieforum.com/forum/vrcc_tech.cgi?noframes;read=1274246

honda service bulletin fix

http://www.goldwingworld.com/pages/sb1.pdf

[RonW]

I though it was for overflow not just a vent.

me, too. also thought the vent tube was double duty.