Fuel Leaking out of Carb, Squirting out of main nozzle....

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Fuel Leaking out of Carb, Squirting out of main nozzle....

over the years I have seen carb bodies and throttle bodies destroyed by soaking couple that with certain coatings wont withstand certain chemicals and no one will say excactly which I quit soaking carb bodies on outboards. as the bodies contain NO fuel there is really no reason to spend the time soaking them on the V yamahas or most any yamaha carb.
maybe the old mercs but the jonnyrudes SPECIFICALLY stated NO SOAKS.
at 75 sets a year I could not make it.
I to have been doing this work for the better part of the past 35 years. you wont believe how many Holleys and Rochesters and webers I have seen the soak tanks tear up.
I have also seen the tank tear up the throttle body assy on HPDI's and the shaft seals on both the 2.6L and the 3.1L carbed motors.
these seals ARE NOT replaceable nor repairable.
thats why I quit years ago.
no one from Yamaha,Merc or suzuki will actually give a chemical reference and no one from the chemical companies will warrenty the soak application.
the best I ever used was an ultrasound cleaner, other than it was slow as molasses.
as I am billing at 85 per hour I try not to waste time on a job that doesnt require it.
most 2.6L v6 motors take just under 2 hours,a v4 about 1.5 a carbed 3.1 about 3, the VST on HPDI or OX66 about 45 min.
the trick is to learn what works for you and your customers and go with it.
kinda like watching in amazement in south america at rinseing Racor filters out in a 5 gallon bucket of gas.
something we would never think of here.
there that gas is about 60 cents for the entire bucket,most likly cheaper than the actual bucket.
the Racor,if actually avalible is almost 65 dollars.
 

fsutim

Seaman
Joined
Oct 18, 2003
Messages
67
Re: Fuel Leaking out of Carb, Squirting out of main nozzle....

what you have demonstrated that out of intake,compression,ign and power the one cycle missing is the intake of the correct air/fuel ratio.
given that fact I would very very strongly suspect the fuel system.
can you get fuel to the pump? can you get fuel to both fuel bowls?
can you move the fuel from the bowl,through the pilot and main jet to the intake track?
can you move air/fuel from the intake to the piston crown?
see where I am going with this?
there is only ONE cause for fuel to leak out of the emulsion nozzle and that is the needle valve for what ever reason failed to seal on the seat.
.

The top carb is no longer leaking fuel. After the top carb was pouring fuel out of the top left main nozzle, I took it off and took out the suspect needle and float and put it back on and checked the float height. After putting the carb back on the engine I now cant start the engine and fuel is no longer leaking out of the carb as it was before I took it off.
 

fsutim

Seaman
Joined
Oct 18, 2003
Messages
67
Re: Fuel Leaking out of Carb, Squirting out of main nozzle....

What the above poster is NOW describing is a lack of fuel in the fuel bowl or he isnt using the choke correctly.
now we gotta find out why.
either the quick connect is blocked,the filter is blocked both carbs have all 4 needles blocked or all four floats are incorrectly set.
remember he is posting now about it will run if a flammable gas is introduced seperatly from the carbs and will run until the combustables are gone.
shows me a lack of fuel in the intake and clyinders.
goes back to what I keep preaching, you MUST understand what each subsystem does and how it can affect the rest of the subsystems in a system.
that and Suck,Squeeze,Bang and Blow.
if all 4 are present it simply runs as designed,if it does not run as desiged figure out which of the 4 is missing.

Should I start by checking the quick connect and fuel filter? How about spraying in a fuel/oil mix into the carbs and seeing if that will allow it to turn over. As you said it seems like a fuel issue, although I'm just not sure where to start.
 

JustJason

Vice Admiral
Joined
Aug 27, 2007
Messages
5,319
Re: Fuel Leaking out of Carb, Squirting out of main nozzle....

Thanks for the info Rodbolt.... I had no idea that that particular carb didn't have a bowl vent..... I thought every carb had to have a bowl vent. I certainly haven't been in every carb ever... so I guess that's my new learned thing of the day. Kudos.

Fsutim.... Do your carbs have drains on the bottom? If so, have you pulled a drain yet to see if fuel came out of the bowl?
If you can squeeze the primer bulb and it firms up.... then either the carbs are filling up properly, or there is a restriction/blockage someplace after the primer bulb but before the needle/seat in the carb.
If the carbs are full.... you should be able to start and run the motor for a minute without the fuel tank even hooked up.
 
Joined
Nov 25, 2008
Messages
26
Re: Fuel Leaking out of Carb, Squirting out of main nozzle....

Shouldn't you be able to maually open the Throtlle, while looking into the Carb and see a spary og fuel?

Les
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Fuel Leaking out of Carb, Squirting out of main nozzle....

at cranking speeds with the choke and the throttle open there simply wont be enough intake vacum to move fuel.
the above suggestions are all valid though,manually drain a bowl to see if it has fuel,manually block off the venturi then crank it to see if fuel can be pulled past the main jet.
what the latest problem description is a lack of fuel/air in the intake track. now we just gotta find out why.
 

fsutim

Seaman
Joined
Oct 18, 2003
Messages
67
Re: Fuel Leaking out of Carb, Squirting out of main nozzle....

Here is the latest, I took both carbs off on Tuesday to check the float height. All carbs were adjusted to .60 which is what my new manual states. I previously had them at .50. When I put the carbs back on I noticed that the fuel lines were interfering with the Carb Throttle Butterfly linkage and most likely wouldnt allow the butterflies to open. I assume this was my previous problem with the engine not wanting to start. Once the carbs were back on the engine the engine started right up, but although running, fuel was leaking from the carbs again. This time it was coming from the bottom left carb (previously top left leaking). I took the carb off and checked the float, took the float off and put it and the needle seat back on and reassembled the carb. When I put the carb back on I started priming the bulb to see if fuel would come out of the carb and sure enough the same carb was spitting fuel out of the main nozzle. I've rebuilt carbs on my previous outboard and never had this problem, apparently i'm making a simple procedure into rocket science. On a side note I have been using a 2 gallon gas tank that I have been putting the fuel line just below the primer bulb directly into to test start the engine. My main tank has old gas in it that needs to be drained so I haven't been using that. I cant imagine that this would be contributing to my problem but I thought I throw it out there. I also read that when I have the carb off I should invert it and blow air through the fuel intake line to make sure the needle is seated and doesn't allow air through it. Any ideas where to go from here?
 

danboatman44

Cadet
Joined
Apr 20, 2009
Messages
19
Re: Fuel Leaking out of Carb, Squirting out of main nozzle....

what happened with this thread come on people?????
 
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