4.3 mercruiser flooding after running and then turning off

[mgeorge15]

I have a 1990 celebrity with a 4.3 mercruiser motor with a 2 barrell carb on it. It runs fine and if you kill it and then start it right back up it fires right up. But if you let it sit for about 3-4 minutes it gets flooded. After you turn they key off it keeps pumping gas into the carb for about 30 seconds or so. Any ideas on what could be wrong??

 

[achris]

Re: 4.3 mercruiser flooding after running and then turning off

Welcome to the club. Almost every 4.3 I know about has this problem. Mercruiser refuse to acknowledge it. The carb manufacturers won't fix it, in fact they say it can't happen! <br /><br />When you find a fix, let me know. Or you could use Bondo's fix, #11-live with it!<br /><br />Chris................

 

[mgeorge15]

Re: 4.3 mercruiser flooding after running and then turning off

ok well thats great, i know it has to be a carb problem, im thinking the float is set too high or something to that matter.

 

[mgeorge15]

Re: 4.3 mercruiser flooding after running and then turning off

Does anybody else have any ideas??

 

[achris]

Re: 4.3 mercruiser flooding after running and then turning off

It's the design of the carb. They dribble because the fuel continues to flow to the aux venturi by capillary action. I have been told by carb 'experts' that it can't happen. They go strangely quiet when I tell them I have watched two different carbs do it.<br /><br />I have even tried running with the fuel level set 3mm lower than spec. Still have the problem.<br /><br />Chris.........

 

[Bondo]

Re: 4.3 mercruiser flooding after running and then turning off

Chris,... He's got the 2bbl.......Not the 4bbl Weber.....<br /><br />Apples,+ Oranges.......<br /><br />Mical,.... Try resetting your float.....On Rebuild the Carb....

 

[mgeorge15]

Re: 4.3 mercruiser flooding after running and then turning off

DOES ANYBODY KNOW THE SPECS FOR THE FLOAT IN THE CARB??

 

[achris]

Re: 4.3 mercruiser flooding after running and then turning off

Opps, just saw '4.3' and 'flooding' and jumped. Sorry.<br /><br />Spec for carb<br /><br />Float level : 9/16" (Measurement taken from the gasket)<br />Float drop : 1-3/32" (Also from the gasket)<br /><br />Chris.

 

[wake5150]

Re: 4.3 mercruiser flooding after running and then turning off

Chris,<br /> Those specs are for the solid needle right? I think it's a bit different for the spring needle?<br /><br />Would the spring needle help this chap out?<br /><br />Wake

 

[achris]

Re: 4.3 mercruiser flooding after running and then turning off

Solid needles are the standard, so I guess those specs are for solids. Don't know about spring loaded. Didn't help me but could work in this case.

 

[mgeorge15]

Re: 4.3 mercruiser flooding after running and then turning off

i adjusted the carb, it was set way too high, works perfect now, thanks for all the help

 

[Bondo]

Re: 4.3 mercruiser flooding after running and then turning off

That's What I Love To Hear.............

 

[terry47]

Re: 4.3 mercruiser flooding after running and then turning off

Hey chris,<br /><br />You say almost every 4.3 has a problem with flooding the carb? I have a similiar problem, 02 volvo 4.3 2brl carb, takes off and runs like a top for hours until you stop. When taking off again and almost coming on plane engine just quits and will not start again on its own. I am thinking the fuel pump is not firing enough to get me out of the water, can it be too much fuel?? <br />Thanks,<br />Texas t

 

[achris]

Re: 4.3 mercruiser flooding after running and then turning off

Sorry Texas T,<br /><br />I am refering to the 4.3l Mercs with 4bbl Webers on them. The problem is the carb. <br /><br />I'm not familiar enough with your engine to make comment, apart from 'check pump pressure and delivery volume'. I don't even know if the pump is mechanical or electric. (I'd guess at electric, but it's only a guess). Try posting a new thread.<br /><br />Chris..........