4.3LX 2bbl stalling at no wake speed after coming off plane

[jkimball]

Hello all, I have a '97 Regal with a 4.3LX 2bbl that's recently started having a stalling problem.
It typically starts just fine at home or at the ramp, and runs great with no hiccups or lack of power. The problem is, occasionally after running it for a while and it getting to operating temp (gauge shows 165*-170*) when I come off plane, if the RPMs drop below say 1200 (maybe even lower?) it will occasionally stall and won't start for a minute or two after that. Granted it always eventually starts, it just takes a minute. And the problem is intermittent but has become more frequent. We just got this boat, traded our trusted OB powered bowrider for it; and I'm starting to catch some flack from the admiral because she's afraid we will get stranded needing a tow
The water/fuel separator was replaced last month also, but I think the mechanic used a Sierra part, not OEM
any help would be great

 

[alldodge]

My guess is your carb is either flooding or running out of gas. When it does this need to see if fuel is leaking into the intake down the throat of the carb. If this is what's happening, need to rebuild the carb, if not suggest checking fuel pressure (3 to 7 psi)

Probably flooding, do you smell gas?

 

[jkimball]

Thanks AllDodge, according to the PO the carb was just rebuilt, and it does look fairly new.
If that's the case, what would cause this to happen (flooding) on a recently rebuilt carb?

 

[Volphin]

Oftentimes it is a defective needle/seat or float height problem. If it was recently rebuilt, check that the carb is securely attached to the intake. A small vacuum leak can cause this as well.

 

[thumpar]

How "recently" was the carb rebuilt? Who did the carb rebuild?

 

[jkimball]

How "recently" was the carb rebuilt? Who did the carb rebuild?

I don't know exactly when it was, I'm only going on the PO's word. Supposedly it has been within the past year

 

[Rick Stephens]

No other mechanical repair is more often done incorrectly and requiring a repeat repair than a carb rebuild. It takes a special amount of care to do it right the first time, and most mechanics tend to skimp.

Things that a freshly rebuilt carb can do to cause your symptoms:

1) If flooding, then the most obvious is float level is not correct. (needs to be right on, not just close)

2) If starving for fuel, same as above, or a bad needle valve, or a plugged port, or a gasket put on wrong or.....


Next time it happens pull the flame arrestor and look, smell, work the throttle once while looking into the bore - does the accelerator pump squirt fuel? Your issue sounds reasonably simple, at least. Not electrical, not a mechanical problem other than in the fuel system.

​Rick

 

[Volphin]

Rick is right! I've seen so many "rebuilt" carbs adjusted incorrectly it would make your head spin. My favorite ones are the ones they disassembled and cleaned with spray cleaner. LOL