Fuel related stall issue 4.3 /carb

[BobH]

I have a 2007 185 sport with carb, and 4.3. The boat runs smooth achieves rpm except when coming off idle. There it stumbles and if you catch the throttle , you can pepper it and get it going.
The boat only has 223 hours , It had the carb rebuilt before I picked it up. I replaced the fuel/water separator , the anti siphon valve and fuel line. Also pulled filter at carb. Does the pick up tube in fuel tank have a filter/sock on the end ?? Any ideas would be helpful.
Thank You,

BobH

 

[Espos4]

Check the accelerator pump for proper operation. It should give a visible extra shot of gasoline as you accelerate off idle.

 

[BillK2632]

+1, sounds like accelerator pump is not adjusted properly - what carburetor do you have - Mercarb 2bbl? If so, the accelerator pump lever has 3 holes that allow you to adjust the amount of fuel the accelerator pump "squirts" on acceleration - if it is bogging on accelerator it's a matter of moving the lever to a different hole - top hole squirts most fuel, bottom hole squirts least.

 

[BobH]

Thanks , I had considered the accelerator pump. I didn't know it was adjustable. Yes the Merc 2 bbl. I will give it the adjustment (Once I find a good parts breakdown )
Still wondering about fuel pick point filter/sock/ ?
Thanks Again,
BobH

Found a manual: http://www.discount-marine.com/club/files/carb.pdf

 

[Lazy Daze]

Yes, the fuel pickup would have a screen on the bottom. But this (and AS valve, the fuel line, etc) is the not the problem. Anything that far away is not going to be the issue. Besides, you would have had more issues if one of those things was the problem.

 

[Wanderer 290]

Has the idle circuit been properly adjusted? A excessively lean setting at idle may cause a stumble coming of idle in addition to a faulty accelerator pump.

 

[BobH]

Thanks for the replies . I wont be able to check things for a week . Will update when this is sorted. I did richen the mixture without any positive results. The boat will fire right back up and idle smooth but when you try to add throttle it will stumble and stall

 

[Espos4]

Next time at the boat, check and see how it responds if you add throttle VERY slowly. If it is smoother and doesn't hesitate as much, that'd be another indication that the accelerator pump may be the culprit.

 

[BobH]

Add insult on to injury. Moved accelerator pump arm to highest hole. Went to start and starter failed, great ! Just got this boat also maybe I've got an hour on her. Not building a trustworthy relationship ! It 223 hours

 

[Lazy Daze]

Check your starter fuse. You may inadvertently shorted something... or maybe it was just the fuse's time to go. After all, it's 14 years old. Truthfully, hours are almost meaningless.

 

[BobH]

Thanks Dave.. I Don't think the fuse/CB is at fault. I will take a another look at that before I pull starter. Currently it will engage and maybe give a groan and solenoid click as it tries to rotate. As a precaution I pulled the spark plugs just in case it was in a liquid lock. Thankfully it was not !

 

[Lazy Daze]

Bob, OK, when you wrote "starter failed", I took that to mean it didn't do anything. IF you're getting some movement, it's not the fuse. But it could be any of the items in the circuit... battery... battery connections... other wire connections... the wires themselves... the starter... relay/solenoid...

How did it crank with the plugs out? And/or did you try cranking it by hand with the plugs out? What happens if you jump the starter (flip the kill switch to off, first, for safety)?

 

[BobH]

same w/o plugs.. tries to crank for a second then click from sol thereafter . I did a batt svc , cleaned all connections , charge batt. did voltage drop with ignition in start/crank position. also did rap on hammer while engaging starter. thanks for the help

 

[Bt Doctur]

LD, I did find a SS meesh screen inside the pickup tube on a motor I was working on

 

[BobH]

Well finally got around to make time for this boat. New starter works fine. Pulled carb and found the float level was about a 1/2 " to high. This has been a lot of aggravation however it forced me to learn my way around the boat. It runs really well now and pulls strong out of the hole.
Now time to work on some cosmetics and enjoy the boat.
Thanks
BobH

 

[hblock72]

Great news.

 

[OpieTaylor]

I've tried the search function, so please forgive me of its been covered, but my 4.3L MPI has hesitation problems on first plane.
I warm it up, accelerate and trim and it really struggles. Max RPM is around 3500.
After a "long" quick few minutes at WOT it runs like a scalded dog right up to 43/4400 RPM's which I think is normal for its 21P prop and 1.62:1 gear ratio. It feels like a cylinder is not producing, or water is in the fuel, but I've changed the fuel/water separator. Pushed on the plug caps to make sure they're seated. It's a 185 Sport 2008.

The power loss seems to be intermittent, it will kick in and you feel +1G's then let off then kick in again, then smooths itself out and all is well until next trip out.

 

[Chip S]

I had the same trouble with a 5.7 GSi engine I had. It was always water in the fuel. Are you adding fuel treatment (Startron, Stabil, etc.) with every fillup? Whenever it happened to me I would add a bottle of Startron to the fuel tank and it would smooth out. If you haven't been adding fuel treatment every time you add fuel you may need to change the fuel filter a couple of times before you get all of the water out. With ethanol fuel you need to add fuel treatment every time. Fuel injected engines are very sensitive to water in the fuel.