Topic: My Petcock is not a well behaved Pet.

[JWilde]

After letting the bike sit for a week, I turned the petcock on before starting, and walked away for about 5 min to do something else. When I got back to the bike, gas was dripping (not sure where from) and pooled beneath the bike.

i ignored it, started up the bike and went on my way. Throughout the day, no petcock or leaking issues. This isnt the first time it has happened (the leak) and ONLY happens after the bike has been sitting for a few days (like 5 or more).

All connections are solid. Hmmmmm....

[SOHC4 Cafe Racer Fan]

FYI - this is exactly why you need to turn the petcock to OFF when you stop your bike.  When in an ON or RESERVE position, gasoline is flowing (via gravity) out of the tank to the carburetors. It can happen if a float doesn't seal completely.

THIS does not happen with a fuel injected bike, where a fuel pump delivers fuel.

NOTE: a puddle/pool of gas is not the safest thing to accumulate under a motorcycle.

[70CB750]

Not sure what carbs you have but on 750 it would be the float valve.

[JWilde]

Not sure what carbs you have but on 750 it would be the float valve.

1972 350F

[mrfish2]

This happens when one of your floats in the carbs doesn't seat all the way and allows gas to fill past the overflow point, thus running into the overflow tube and routed under the bike.

[JWilde]

This happens when one of your floats in the carbs doesn't seat all the way and allows gas to fill past the overflow point, thus running into the overflow tube and routed under the bike.

Hmm. Thanks! Always more to learn! Whats the fix for this, and why does it happen only after long periods of sitting?

[SOHC4 Cafe Racer Fan]

This happens when one of your floats in the carbs doesn't seat all the way and allows gas to fill past the overflow point, thus running into the overflow tube and routed under the bike.

Hmm. Thanks! Always more to learn! Whats the fix for this, and why does it happen only after long periods of sitting?

Again, if you have the petcock open, you are creating a feed of gas into the carburetors. Over time, this can cause the gas to accumulate (especially if the float is not completely closed).  THE FIX IS: TURN OFF YOUR PETCOCK.

[flybox1]

If the pet has been OFF, and you turn it on and it starts peeing gas,  tap the carb stay plate to free up the stuck float, if that is all it is.
(^^^ will happen more if you only have a side stand, which puts one float in gas and the other out)
If there is debris in the gas, holding the float valve open, the only fix is to clean your tank and ensure you have a good, working fuel filter(in-tank or in-line)

[JWilde]

This happens when one of your floats in the carbs doesn't seat all the way and allows gas to fill past the overflow point, thus running into the overflow tube and routed under the bike.

Hmm. Thanks! Always more to learn! Whats the fix for this, and why does it happen only after long periods of sitting?

Again, if you have the petcock open, you are creating a feed of gas into the carburetors. Over time, this can cause the gas to accumulate (especially if the float is not completely closed).  THE FIX IS: TURN OFF YOUR PETCOCK.

You didnt read carefully. Thats not it. Let me again explain the dynamic:

I am VIGILANT about making sure my petcock is on and off when it needs to be.

WHEN I PUT MY BIKE IN THE GARAGE with the petcock in the OFF position, when I next go to turn it on, after letting it sit five days or more, ONLY THEN does it leak.

Ive got most of the bike thing down now so not quite so newbie as to not know how to work the petcock, but i thank you for your advice

[JWilde]

If the pet has been OFF, and you turn it on and it starts peeing gas,  tap the carb stay plate to free up the stuck float, if that is all it is.
(^^^ will happen more if you only have a side stand, which puts one float in gas and the other out)
If there is debris in the gas, holding the float valve open, the only fix is to clean your tank and ensure you have a good, working fuel filter(in-tank or in-line)

Thanks! I put a good helping of MMO in the gas each time I fill it, so I hope that helps. Will do as you say!

[Scott S]

 You just have to do a little detective work and figure out where it's leaking from. Do you see gas around the petcock/tank connection? Where the fuel lines go from the petcock into the carbs?
 More likely, it's coming from one of the overflow hoses on the bottom of the float bowls. There should be hoses that run down the back of the engine and between the swing arm pivot....then point towards the ground. It can be a little tough to figure out what hose goes to what bowl, but that will tell you which carb has the sticky float.

 I say do some detective work because you said "When I got back to the bike, gas was dripping (not sure where from) and pooled beneath the bike. "  It could be coming from above and running all the way down. Try to figure out exactly where it's leaking and you can get better advice on what to check next.

 Most likely culprit: sticky float and fuel valve in the carb(s). Tap on the float bowls with the handle of a screw driver and it will usually stop.

 If you're turning off the petcock when you park the bike you're doing the right thing.
 There are different schools of thought about running the bowls low or empty before turning it off. Some say leave gas in them to keep the O-ring lubed, others say run it dry so that the ethanol fuel doesn't cause issues with the internals.

[JWilde]

You just have to do a little detective work and figure out where it's leaking from. Do you see gas around the petcock/tank connection? Where the fuel lines go from the petcock into the carbs?
 More likely, it's coming from one of the overflow hoses on the bottom of the float bowls. There should be hoses that run down the back of the engine and between the swing arm pivot....then point towards the ground. It can be a little tough to figure out what hose goes to what bowl, but that will tell you which carb has the sticky float.

 I say do some detective work because you said "When I got back to the bike, gas was dripping (not sure where from) and pooled beneath the bike. "  It could be coming from above and running all the way down. Try to figure out exactly where it's leaking and you can get better advice on what to check next.

 Most likely culprit: sticky float and fuel valve in the carb(s). Tap on the float bowls with the handle of a screw driver and it will usually stop.

 If you're turning off the petcock when you park the bike you're doing the right thing.
 There are different schools of thought about running the bowls low or empty before turning it off. Some say leave gas in them to keep the O-ring lubed, others say run it dry so that the ethanol fuel doesn't cause issues with the internals.

from now on I think I will belong to the "run dry" school. Just before I park Ill starve the carbs.

Thanks for yoru guidance! Super helpful!!!

[mrfish2]

Thanks! I put a good helping of MMO in the gas each time I fill it, so I hope that helps. Will do as you say!

A "good helping?" Probably not such a good idea, they say to only use 4oz to every 10 gallons of gas. And if your engine and carbs have both been rebuilt then there really isn't any need to put MMO in the gas.

[Scott S]

 MMO is the least harmful of any additive, but all you need for our Honda's is a cap full or shot glass worth per full tank.

  I've been able to determine on all my bikes when to turn off the petcock to get the bowls empty. I know just about how many blocks, miles, turns, etc. from home to turn it off.
 I'm lucky enough to get ethanol free gas around here now and don't worry about running them low/empty too much anymore. But I sure did when I was running ethanol laced fuel.

[JWilde]

Thanks! I put a good helping of MMO in the gas each time I fill it, so I hope that helps. Will do as you say!

A "good helping?" Probably not such a good idea, they say to only use 4oz to every 10 gallons of gas. And if your engine and carbs have both been rebuilt then there really isn't any need to put MMO in the gas.

Just a habit I learned from my dad with our old cars.

[flybox1]

Thanks! I put a good helping of MMO in the gas each time I fill it, so I hope that helps. Will do as you say!

A "good helping?" Probably not such a good idea, they say to only use 4oz to every 10 gallons of gas. And if your engine and carbs have both been rebuilt then there really isn't any need to put MMO in the gas.

Just a habit I learned from my dad with our old cars.

This is not an old American car.

[JWilde]

Thanks! I put a good helping of MMO in the gas each time I fill it, so I hope that helps. Will do as you say!

A "good helping?" Probably not such a good idea, they say to only use 4oz to every 10 gallons of gas. And if your engine and carbs have both been rebuilt then there really isn't any need to put MMO in the gas.

Just a habit I learned from my dad with our old cars.

This is not an old American car.

Indeed. And now I stand informed.

[SOHC4 Cafe Racer Fan]

This happens when one of your floats in the carbs doesn't seat all the way and allows gas to fill past the overflow point, thus running into the overflow tube and routed under the bike.

Hmm. Thanks! Always more to learn! Whats the fix for this, and why does it happen only after long periods of sitting?

Again, if you have the petcock open, you are creating a feed of gas into the carburetors. Over time, this can cause the gas to accumulate (especially if the float is not completely closed).  THE FIX IS: TURN OFF YOUR PETCOCK.

You didnt read carefully. Thats not it. Let me again explain the dynamic:

I am VIGILANT about making sure my petcock is on and off when it needs to be.

WHEN I PUT MY BIKE IN THE GARAGE with the petcock in the OFF position, when I next go to turn it on, after letting it sit five days or more, ONLY THEN does it leak.

Ive got most of the bike thing down now so not quite so newbie as to not know how to work the petcock, but i thank you for your advice

JW:  Please don't be so touchy.  I am actually trying to help and I DID read your initial post carefully.  You said that this happens when you leave your petcock on sitting for 5 plus minutes.  It won't happen if you turn the petcock OFF when the bike is not running.

After letting the bike sit for a week, I turned the petcock on before starting, and walked away for about 5 min to do something else. When I got back to the bike, gas was dripping (not sure where from) and pooled beneath the bike.

Granted, this issue usually happens more often when people just leave their petcock on after a ride.  Since your leak is more immediate and acute it is likely a float sticking. 

Contrary to your thread topic, this does NOT sound like a petcock issue.

[JWilde]

This happens when one of your floats in the carbs doesn't seat all the way and allows gas to fill past the overflow point, thus running into the overflow tube and routed under the bike.

Hmm. Thanks! Always more to learn! Whats the fix for this, and why does it happen only after long periods of sitting?

Again, if you have the petcock open, you are creating a feed of gas into the carburetors. Over time, this can cause the gas to accumulate (especially if the float is not completely closed).  THE FIX IS: TURN OFF YOUR PETCOCK.

You didnt read carefully. Thats not it. Let me again explain the dynamic:

I am VIGILANT about making sure my petcock is on and off when it needs to be.

WHEN I PUT MY BIKE IN THE GARAGE with the petcock in the OFF position, when I next go to turn it on, after letting it sit five days or more, ONLY THEN does it leak.

Ive got most of the bike thing down now so not quite so newbie as to not know how to work the petcock, but i thank you for your advice

JW:  Please don't be so touchy.  I am actually trying to help and I DID read your initial post carefully.  You said that this happens when you leave your petcock on sitting for 5 plus minutes.  It won't happen if you turn the petcock OFF when the bike is not running.

After letting the bike sit for a week, I turned the petcock on before starting, and walked away for about 5 min to do something else. When I got back to the bike, gas was dripping (not sure where from) and pooled beneath the bike.

Granted, this issue usually happens more often when people just leave their petcock on after a ride.  Since your leak is more immediate and acute it is likely a float sticking.

Sorry about being touchy but ppl in this forum have pounced before for no reason, so Im guarded. And I also hate explaining myself over and over.

The thing is, like i said, this is the only time this happens (when the bike has sat). Usually leaving a petcock on OVERNIGHT will result in flooding, not leaving it on for 5 min.
I once left my petcock on for 15 min while the bike was sitting and I was getting some food, and this didnt happen. its specific to the bike having sat for 3 or more days, turning it on, and then it overflowing.

[Davez134]

Yes, the most likely (and probably easiest fix) is a sticking float. Another thing to check, after determining if the float is sticking or not is condition of float needle/seat. If worn, or if any debris from the fuel/tank get in between the two, it cant seal properly. (even if the float itself is moving properly.

Also, double check the float level set height. I know this can be a PITA finding a leak.

[JWilde]

Yes, the most likely (and probably easiest fix) is a sticking float. Another thing to check, after determining if the float is sticking or not is condition of float needle/seat. If worn, or if any debris from the fuel/tank get in between the two, it cant seal properly. (even if the float itself is moving properly.

Also, double check the float level set height. I know this can be a PITA finding a leak.

To be honest its not a big deal and only happens when the bike has sat for a long time. I dont give a #$%*. As long as its not leaking when the bike is mobile and as long as it doesnt blow up.

[70CB750]

HAHAHA.  I ride for about 30 years and still forget to turn petcock off or on, there is no such thing as always, it happensd to all of us.

This happens when one of your floats in the carbs doesn't seat all the way and allows gas to fill past the overflow point, thus running into the overflow tube and routed under the bike.

Hmm. Thanks! Always more to learn! Whats the fix for this, and why does it happen only after long periods of sitting?

Again, if you have the petcock open, you are creating a feed of gas into the carburetors. Over time, this can cause the gas to accumulate (especially if the float is not completely closed).  THE FIX IS: TURN OFF YOUR PETCOCK.

You didnt read carefully. Thats not it. Let me again explain the dynamic:

I am VIGILANT about making sure my petcock is on and off when it needs to be.

WHEN I PUT MY BIKE IN THE GARAGE with the petcock in the OFF position, when I next go to turn it on, after letting it sit five days or more, ONLY THEN does it leak.

Ive got most of the bike thing down now so not quite so newbie as to not know how to work the petcock, but i thank you for your advice

[Davez134]

True its not a big deal now the way you're describing, but leaks usually get worse over time. If you find the problem now before it becomes an issue, it will be one more thing you've learned. Plus, Hondas shouldn't leak

[SOHC4 Cafe Racer Fan]

True its not a big deal now the way you're describing, but leaks usually get worse over time. If you find the problem now before it becomes an issue, it will be one more thing you've learned. Plus, Hondas shouldn't leak

Being a firefighter, Dave prefers that we do not have gasoline pooling underneath our vehicles, especially in our garages.

[BomberMann650]

You don't have a serious problem until your bike does this in the OFF position.

P.S.  That isn't mtn dew