1988 4.3L Mercruiser with Mercarb dumps gasoline into carburetor throat at shutdown

[dancewithme951]

As in title, the fuel dumping seems to then flood the engine so that each restart - even when engine is warm - requires cold start procedure (throttle forward to set choke, etc.) Is float possible sticking? It runs great once started just always hard to start.

 

[Bondo]

Re: 1988 4.3L Mercruiser with Mercarb dumps gasoline into carburetor throat at shutdo

Ayuh,.... Welcome Aboard,.... What carb ya got,..??

Sure sounds like it's in need of a Rebuild, regardless which carb ya got,...

 

[Walt T]

Re: 1988 4.3L Mercruiser with Mercarb dumps gasoline into carburetor throat at shutdo

Fuel boiling possibly, that will cause that symptom

 

[dancewithme951]

Re: 1988 4.3L Mercruiser with Mercarb dumps gasoline into carburetor throat at shutdo

ayuh,.... Welcome aboard,.... What carb ya got,..??

Sure sounds like it's in need of a rebuild, regardless which carb ya got,...

3304-9565a1

 

[dancewithme951]

Re: 1988 4.3L Mercruiser with Mercarb dumps gasoline into carburetor throat at shutdo

Fuel boiling possibly, that will cause that symptom

So how does one deal with fuel boiling?

 

[dancewithme951]

Re: 1988 4.3L Mercruiser with Mercarb dumps gasoline into carburetor throat at shutdo

Ayuh,.... Welcome Aboard,.... What carb ya got,..??

Sure sounds like it's in need of a Rebuild, regardless which carb ya got,...

Me again Bondo. On an older post I read earlier today you suggested a poster upgrade Mercarb like mine to the newer on with bowl.main body as one unit (I may be confusing the pieces). Where could I find that carburetor and, apart from obvious improvement in disassembly/reassembly with fewer parts, any other advantages?

 

[Bondo]

Re: 1988 4.3L Mercruiser with Mercarb dumps gasoline into carburetor throat at shutdo

Me again Bondo. On an older post I read earlier today you suggested a poster upgrade Mercarb like mine to the newer on with bowl.main body as one unit (I may be confusing the pieces). Where could I find that carburetor and, apart from obvious improvement in disassembly/reassembly with fewer parts, any other advantages?

Ayuh,.... I think yer creditin' Me, with somebody else's advice,.... Sounds like ya got the 2 bbl. carb,....

I like the Merc/ Weber 4bbl. which is a carbon copy of the Edlebrock Performer 1409, which makes both carbs Carter AFB Clones,...

I rarely putz with the 2bbl.s,... there's several threads goin' on 'bout 'em,...
Hopefully 1 of the guys that Knows 'em, will catch this 2bbl. Mercarb problem,...

Now,.... If ya wanta bolt on 20hp by goin' to a 4bbl. carb,....

I'll do my Best to walk ya through it,....... :lol: :laugh:

 

[ktbarrentine]

Re: 1988 4.3L Mercruiser with Mercarb dumps gasoline into carburetor throat at shutdo

I had a similar problem with carb flooding that was caused by a bad fuel pump diaphram, putting fuel into the carb via the sight flow tube. Wouldnt notice it when running, but caused it to have flooded symptoms when trying a hot restart. May not be your prob, but have you checked the sight-flow tube during operation?

 

[dancewithme951]

Re: 1988 4.3L Mercruiser with Mercarb dumps gasoline into carburetor throat at shutdo

I'll check that. When should there NOT be fuel flowing in the tube?

 

[dancewithme951]

Re: 1988 4.3L Mercruiser with Mercarb dumps gasoline into carburetor throat at shutdo

Sounds like more than I could manage...new manifild, etc. I just thought there was a newer 2bbl that wa simpler in design than my 1989 Mercarb that might be worth swapping for. Thanks though for your help.

 

[ktbarrentine]

Re: 1988 4.3L Mercruiser with Mercarb dumps gasoline into carburetor throat at shutdo

I'll check that. When should there NOT be fuel flowing in the tube?

There should never be fuel in the sight-flow tube..... unless the fuel pump diaphram has failed, in which case it is doing its job to keep fuel out of the crankcase and to alert you to the need to get a new fuel pump.

 

[dancewithme951]

Re: 1988 4.3L Mercruiser with Mercarb dumps gasoline into carburetor throat at shutdo

Thanks...something I'll definitely check next outing!!