leaking fuel

[chiz]

Today I fixed a leak but I really don't know how. Pissing fuel out of the right hand carb overflow gave it a few whacks ....did not stop
     Removed tank, fuel pissing out of tap in run and prime position undid the diaphragm screws on what appears to a new gas tap poked around in there for a few minutes.   
   Put the tap diaphragm back on and suddenly no more flow out of the tap. Removed right float bowl and poked around in there for a few minutes put the whole mess back together and rode home ....no further leaks.
     Was/is the float needle/seat suspect on that carb or is the gas valve just fooling or both???
  Chiz 

[FJmonkey]

Just some crap in the seat, seems like its flushed out.

[theLeopard]

I it leaks out your ADC solenoid just gut it.
Fuck em. Take it from Randy, that emissions shit aint worth a hot minute.

[ribbert]

Today I fixed a leak but I really don't know how. Pissing fuel out of the right hand carb overflow gave it a few whacks ....did not stop
     Removed tank, fuel pissing out of tap in run and prime position undid the diaphragm screws on what appears to a new gas tap poked around in there for a few minutes.   
   Put the tap diaphragm back on and suddenly no more flow out of the tap. Removed right float bowl and poked around in there for a few minutes put the whole mess back together and rode home ....no further leaks.
     Was/is the float needle/seat suspect on that carb or is the gas valve just fooling or both???
  Chiz 

The FJ's are all prone to the occasional bout of incontinence, regardless of what shape your carbs are in it has likely developed this:



This indentation is where the needle contacts the tang on the float and is quite defined.

Polish this out and your sticking floats and carb leaking woes should be behind you.

Noel

[rlucas]

The FJ's are all prone to the occasional bout of incontinence, regardless of what shape your carbs are in it has likely developed this:

<pic deleted to avoid repetetive redundancy>

This indentation is where the needle contacts the tang on the float and is quite defined.

Noel

This might be nit-pickery, but since we know how sensitive these carbs can be, wouldn't this little divot also affect float height to some minor extent?


rossi

[ribbert]

The FJ's are all prone to the occasional bout of incontinence, regardless of what shape your carbs are in it has likely developed this:

<pic deleted to avoid repetetive redundancy>

This indentation is where the needle contacts the tang on the float and is quite defined.

Noel

This might be nit-pickery, but since we know how sensitive these carbs can be, wouldn't this little divot also affect float height to some minor extent?


rossi

Technically, by a bee's dick. Practically, no.

Noel

[chiz]

Thing is I don't know why the fuel tap would  decide to flow continuously this is a safety item where in a crash and no vacuum is present at the valve in theory the fuel is supposedto shut off. Had this valve been working it is likely the carb would not have leaked this is not to say that the particular carb does not have a problem,
     Regardless I fixed the tap flow problem but am at loss as to what and how I fixed it....likewise if there was still continuous flow from the tank I am not too sure if the carb would leak or not.

[FJmonkey]

If I read correctly, you have an '84 FJ right? Your OEM petcock has two positions. On and PRI. Make sure it in the "On" position, In Prime it will flow like a wide open valve. In the "On" position it should only flow with the engine running.

[Pat Conlon]

Today I fixed a leak but I really don't know how. Pissing fuel out of the right hand carb overflow gave it a few whacks ....did not stop
     Removed tank, fuel pissing out of tap in run and prime position undid the diaphragm screws on what appears to a new gas tap poked around in there for a few minutes.   
   Put the tap diaphragm back on and suddenly no more flow out of the tap. Removed right float bowl and poked around in there for a few minutes put the whole mess back together and rode home ....no further leaks.
     Was/is the float needle/seat suspect on that carb or is the gas valve just fooling or both???
  Chiz 

As Monkey said ^^

If your petcock was in the "prime position" and fuel was flowing, it was doing exactly what it should be doing.... The "on" position will stop the fuel flow until a vacuum signal from your engine opens the petcock.

If you left the petcock in the prime position chances are high that you will flood your engine and garage floor.

[jscgdunn]

I have seen the same as Noel regarding FJ incontinence (not sure about his);  I have rebuilt four sets so far, and I always splurge on new needle and seat valves.   Even so, they sometimes stick open and leak, usually after it has been sitting for a while (ie in winter up here);  usually just turning the bike off (ie fuel pump) stops the leaking.  On restart leakage does not re-appear.

Jeff

[Mark Olson]

Chiz,

Your tank valve was sticking in the open position .. you should apply some vacuum and test it's operation . It should only flow fuel in on position when vac is applied . Prime flows all the time.

I sounds like one of the carbs has a bad/ dirty seat that may have cleared up with you messing with it.

So yes you had two problems and may have fixed them both by just moving things around.

Please make sure the tank valve is working correctly as this is a safety item as you stated. Also if the fuel is allowed to flow past the tank valve and into the carbs with a bad seat this can fill up your cylinders with fuel and make the engine hard to turn over resulting in you using jumper cables and bending the rods in your Fj. (personal experience of my fj's P.O.)   

[Goody]

Today I fixed a leak but I really don't know how. Pissing fuel out of the right hand carb overflow gave it a few whacks ....did not stop
     Removed tank, fuel pissing out of tap in run and prime position undid the diaphragm screws on what appears to a new gas tap poked around in there for a few minutes.   
   Put the tap diaphragm back on and suddenly no more flow out of the tap. Removed right float bowl and poked around in there for a few minutes put the whole mess back together and rode home ....no further leaks.
     Was/is the float needle/seat suspect on that carb or is the gas valve just fooling or both???
  Chiz 

just had the same problem on my 91, only just had carbs rebuilt about 1000ks or so ago came home after work one evening to the smell of petrol from the gararge. There was a leak from one of the carbs . Cleaned the mess up started the FJ warmed it up turned it off , leak gone . Have yet to ride it (maybe a blast today ) but solfar so good. It's niice to hear about the inconvenience issues. Never new that . The rebuild was well overdue and had two carbs leaking at that stage. Been fine up to now will keep an eye on it .