prevent dreaded Hydrolock

[wobray]

Can this be prevented? What are the causes?
Thanks

[JC]

Hydrolock occurs when fuel leaks into a cylinder while it isn't running, then a start is attempted which because of the fuel in the cylinder, causes the engine to not turn, but break the starter gearing instead. A leaking petcock and stuck float valve are generally both required for this to happen.

To prevent it you must simply keep fuel from flowing when the engine is not running. Turning off the petcock may not always work, and many have changed from the OEM to a Pingle petcock as a way to reduce the chance. Others, including myself, have elected to install an electric fuel flow valve that only allows fuel to flow when the key is on. The Dan Marc is a popular one. Search the board for more information than you really need on the subject.

[Robert]

Hydraulic lock is exactly what the name implies, gas gets into a cylinder and since liquid cannot be compressed when you go to start the engine the piston tries to compress the gas/liquid cannot do it and stops while the starter is going. This breaks the starter gears and you have to take the engine apart. This happens in 2 ways with the latter being the most frequent. The petcock diaphragm fails and it doesn't stop the fuel and worse fuel bypass the diaphragm and goes into the vacuum tube to #6 cylinder. The other more prevalent way is fuel bypasses the petcock because it doesn't shut off the fuel. Then the carb needles fail to stop the fuel and the fuel continues to flow while the bike is stopped. Either way leads to the same result.
   To fix it you can 1 replace the fuel shutoff valve 2 put in the electric valve or 3 get a belly tank. These are all in addition to taking apart the carbs and replacing the carb needles which most dont do. Along with installing a filter of choice in line from the fuel source.

[Patrick]

The answer is no ! But, you help prevent it.. A lot has been written about this subject or the past 15 years..  I believe the best prevention is a Pingle valve, fuel filter, and tapping the start button.. There is enough fuel below the shut-off to lock a cylinder regardless of what others may say.. Working the start button correctly will prevent damage..

[biguglyman]

tapping the start button

Could you elaborate on this?  How you do it and why it works?  Thanks

[jmann]

tapping the start button

Could you elaborate on this?  How you do it and why it works?  Thanks

I believe what he is referring to is tapping the start button prior to starting the girl up. If she clunks it might mean a fuel filled cylinder. If it rolls normal she's GTG. By just tapping you at least give yourself a chance to not over stress the starter gear and cause damage there. You have to be conscious though if you hear the clunk sound to trust your instincts and not hit the button again. Pull the plugs and crank over to purge the offensive cylinder.

[Patrick]

Yep, Jmann got got it right.. I don't think its ever taken more than 2 taps to get her running.. If you hear the dreaded 'clank' , pull ALL the sparklers and clear the cylinder and you're good to go, until the next time..
I don't worry about fuel-locks.. I had the first about 12-13 yrs ago, installed a Pingle and fuel filter[ after converting the original to manual and finding out the damn thing still leaked].. I've been turning the fuel off for 52 yrs so its kind of a habit by now.. After changing a fuel filter last year, some crud[technical term] or varnish must have broken loose and tried to get into #2 cylinder.. I flushed the carburetors and especially #2 half dozen times after having as many fuel-locks on that cylinder in as many days.. Either the crud/varnish was finally flushed from the needle or the Sea-Foam did its job and dissolved it.. I was determined to fix it without removing the chamber, although removing it would have been quicker.. The starter drive gear/pinions haven't been damaged,,, yet..
I think what happens is, when the starter decides to stop spinning the motor the operator decides to press the button really really hard and fast thinking the starter just may spin even harder or faster.. Its just human nature, I guess..

[custom1]

Just be very careful when you pull the spark plugs and crank it over to clear the cylinders. Whichever one is full will spray fuel a long way. Don't want to be doin that inside your garage. Even if you push it in gear, it will spray out. I cranked over a V6 jeep motor one time with the plugs out(doing a compression test) and a plug wire was near the block. I forgot to disable the coil. It got interesting real quick when some fuel came out of the spark plug hole and ignited. 

[Fritz The Cat]

Got a question about the electric valve.

I'm thinking it's just as likely that trash will hold it open as it will the carb floats. Am I right or wrong?

[2step]

What if you shut off your petcock valve 4 or 5 miles before you get home and run most of the fuel out of the carbs, would that not prevent the hydrolok??

[John U.]

Got a question about the electric valve.

I'm thinking it's just as likely that trash will hold it open as it will the carb floats. Am I right or wrong?

That's been my thinking also. It seems to me that periodic inspection of the tank insides and tank cleaning should be added to the list of preventative measures.
The petcock screen has proven not to be sdequate.

[RonW]

What if you shut off your petcock valve 4 or 5 miles before you get home and run most of the fuel out of the carbs, would that not prevent the hydrolok??

a leaky petcock valve will still leak even in the off position and continue to leak overnight. "OFF" is just a label in this context.

[Chiefy]

What if you shut off your petcock valve 4 or 5 miles before you get home and run most of the fuel out of the carbs, would that not prevent the hydrolok??

a leaky petcock valve will still leak even in the off position and continue to leak overnight. "OFF" is just a label in this context.

And just because the engine quits with the valve off doesn't mean much.  The engine is going to suck gas out of the system much faster then a pinhole leak will put it back into the system.

[big bear craig]

I have ordered the Pingle valve, and I'm going to also install a fuel filter and Dan Marc valve.  Could somebody tell me which model of the Dan Marc valve is being used?  Thanks.

[salty1]

Big bear the one below is often mentioned as being used in installs.

http://www.dan-marcrvparts.com/12vomufushof.html

Does anyone know the size of the fuel line fittings needed to mate up to the Valk fuel line?

[Thrud]

I understand the major difference between the Pingel petcock and the stock petcock is the length of the pickup tube.  To be specific, the shorter fuel pickup tube with the Pingel gives you a smaller reserve fuel capacity.  What Pingel mods have folks in this group done to restore the reserve capacity to normal?

Thanks,
Steve

[big bear craig]

Big bear the one below is often mentioned as being used in installs.

http://www.dan-marcrvparts.com/12vomufushof.html

Does anyone know the size of the fuel line fittings needed to mate up to the Valk fuel line?

Thanks for the info.  Just ordered one.

[98valk]

Can this be prevented? What are the causes?
Thanks

posted this about 10 times now.
carb bowls heat up after shutdown the fuel expands, if the bowl vent tube is blocked or not correctly sloped, the fuel has no where else to go except up the needle well and into the carb throat and then down the into a cylinder. a vent line has to be installed like a gravity drain line except in reverse order to atmosphere for it to work, in other words no traps/low points in the line.
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 spotfills 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 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