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skilew
03-08-2005, 06:18 PM
My carb seems to have excess gas dripping into the bowl when it is shutdown. It dripps so much gas after shutting down that the carb actually will start to leak out onto the engine. But the boat seems to be running very well? Any thoughts to this problem.

MarkP
03-08-2005, 06:24 PM
Iím not a mechanic but my first thought would be that thatís not right.. What year/motor/carb??

east tx skier
03-08-2005, 06:30 PM
Sorry, I specialize in hot stalls. But I agree with Mark that those are not favorable symptoms.

Bongo
03-08-2005, 06:32 PM
As with Mark, I'm not a mechanic - though do tinker some with my MasterCraft and an old Pontiac Convertible.

I expect you've got a Holley carb. of some type. I suspect your problem is with the floats in the carb, either stuck or set wrong, or the fuel pressure from your fuel pump is too high.

Bongo

whitedog
03-08-2005, 08:23 PM
Sounds like a stuck float or needle valve.

Laurel_Lake_Skier
03-08-2005, 10:00 PM
It dripps so much gas after shutting down that the carb actually will start to leak out onto the engine. ....... Any thoughts to this problem.
As has been said, it sounds like the float. In any case, due to the potential for a fire in the engine box, you should get it taken care of ASAP.
Keep that blower running! :eek:

MarkP
03-08-2005, 10:37 PM
Hey

Did we ever figure out what kind of boat we are fixin here:uglyhamme

skilew
03-09-2005, 09:26 AM
It is a Holley carb on a 1993 Ford 351. I agree that it sounds like a float problem so how do I adjust. Does the carb have to be completely rebuilt?

ski_king
03-09-2005, 09:31 AM
The orginal carb on the 93 era is known to have issues and many have replaced it with a different carb. Doug, East Tx Skier and others with 93's, will be able to give you info on this.

jsonova99
03-09-2005, 09:38 AM
I noticed something similar to this on my '91 with the 351 engine. Milkmania had this probelm and he just replaced some gaskets in the carb (see the post for more details). I forget what the thread was, I think it was under "Cadilac LQ9 piece of S*#T". I just noticed this on mine, I cleaned everything up but haven't had a chance to run it since, to monitor any leaks. I'd be curious to hear what you find the problem to be though and what the fix is. I keep hearing people having problems with the Holley carb on the '91 and similar year 351 engines.

east tx skier
03-09-2005, 11:32 AM
The orginal carb on the 93 era is known to have issues and many have replaced it with a different carb. Doug, East Tx Skier and others with 93's, will be able to give you info on this.

Although the 4010 on the 93 boats were troublesome, this doesn't resemble the issues I had with mine.

Storm861triple
03-09-2005, 01:11 PM
It's a:
*stuck needle/seat (most likely)
*mis-adjusted float (2nd most likely)
*Too high fuel presure (very unlikely)
...regardless of carb model.

-Tom

Lance
03-09-2005, 01:35 PM
Where specifically is the fuel leaking from? If it was a stuck float it would be pushing fuel into the venturi wouldn't it?... if this is the case it would be just leaking into the intake manifold not onto the engine block? If it is actually leaking on the engine block it makes me think that it is in the fuel passage leading into the bowls (on the 4160 this would be the fuel line into the front bowl or the passage between the bowls).

I

jsonova99
03-09-2005, 02:25 PM
mine seem so be just on the intake manifold

Hunterb
03-09-2005, 03:15 PM
I just went through a carb issue and solved it with some help from the people on this site.

I'm not sure if I'm understanding your problem exactly. I cannot see how a high float level or stuck needle valve could cause fuel to actually leak out of the carb and onto the motor. How is the fuel actually getting on the motor? It can't come over the top of the carb, so where is it escaping from? There is no pressure from the fuel pump when the motor is shut down. Any fuel leaking into the carb as the result of a high float or stuck needle would simply run into the intake manifold, I think anyway. I'm not a carb expert but I really can't see how the fuel can get out of the carb and onto the motor from a stuck needle of high float level situation.

I would suspect that you have a gasket or O-ring problem somewhere. It may be worth buying a Holley 'Renew' kit. They are about $30.00 and come with all the gaskets, o-rings, needle valves and seats etc. They are quite easy to install, at least on a 4160 carb. I think your carb may have externally adjustable floats. Does it have the little sight windows on the side of the bowls? If it does then it's easy to check the float level. If not, as is the case with the 4160, then you have to remove the bowl to adjust the floats.

Good luck with the diagnosis. Make sure you fix up that leak before you drive too far !!!!!! :eek:

Bruce

Storm861triple
03-09-2005, 08:12 PM
I cannot see how a high float level or stuck needle valve could cause fuel to actually leak out of the carb and onto the motor.

The original poster said that it was "dripping into the bowl" I THINK he meant the barrels, and that would be caused by needle/seat, float level WAY off, sunken float (forgot that one earlier) or too high fuel pressure.

Now we're getting confused because jsonova99 jumped on and started talking about his carb leaking onto the intake, which is a completely different symptom and problem. That IS infact a float bowl gasket, or the accelerator pump diaphragm.

We need the original poster to clarify where there is gasoline flowing.

Lance
03-09-2005, 10:35 PM
I agree that we need more infor from original poster but he did say that it leakes until it 'will start to leak out onto the engine'. You would have to leak a lot inside the barrels to make this happen (like enough to fill the intake manifold and the cylinders). I agree that this doesn't seem to be a stuck float.

My one experience with leaking fuel onto the engine was after I rebuild my carburetor and fuel flowed from the little transfer tube that sends fuel from the front to the rear bowl (on a 4160) and was caused by a cut o-ring on the transfer tube.

Hunterb
03-10-2005, 03:04 PM
I agree, more info needed for sure. He does indicate that the fuel ends up leaking onto the motor somehow. It's not possible for the carb to leak enough fuel into the bowls to have it overflow and I can't see how the fuel pump has any effect since the motor is off. Fuel cannot escape from the carb unless there is a bad gasket or o-ring somewhere. Even a high float level or stuck needle will not result in a large amount of fuel leaking into the carb throat when the motor is off as it requires vacuum to get pulled out of the bowl.

The more I think about it the more convinced I am that this is a gasket problem. Why it's not leaking when the motor is running is another question. Maybe it is and evaporates quickly due to the heat. I hope he's using his blower and doesn't have any non-marine parts in there.

Bruce

jsonova99
03-10-2005, 03:32 PM
Sorry I didn't mean to jump in, it just caught my interest because I've noticed a possible leak on my carb, too.

skilew
03-14-2005, 07:16 PM
The carb was leaking out the venturi into the barrel.

Thanks to everyone for their help!

Fixed carb this weekend. Adjusted float and cleaned needle valve and seat. Just like everyone said and this seemed to have fix the problem.

Now how do I adjust the air idle screws if it is needed?

And In case I over adjusted the float does anyone know what the symptoms are if the float is set too low?

Storm861triple
03-16-2005, 08:44 PM
The symptoms of low float level are lean running at all throttle positions. It would have to be pretty far off to affect it noticably though.

To adjust the idle screws start at 1.5 turns out, and turn each on in and out, one at a time, trying to achieve the best idle you can. After you get there, reset your idle speed (throttle stop) and do it again as closing the throttle stop will make the idle mix screws more sensetive.

-Tom