mercruiser carb flooding

[itstim2]

I have a 1988 3.0L Alpha One project boat I'm working on. Carb was flooding (mcm carb mdl # 1389-9562) so I bought the carb kit (sierra # 18-7098) and float (18-7202). Cleaned and blew out the carb and installed the parts and set the float to specifications still floods no wait it DUMPS! Gas pours down the throat from the venturi. The choke system seems to be functioning normally. The gas tank needs cleaning so I'm using a temp tank that utilizes the bulb you have to pump to get fuel to the fuel pump. My question is what, other than the float can cause flooding?

 

[itstim2]

Re: mercruiser carb flooding

I have a 1988 3.0L Alpha One project boat I'm working on. Carb was flooding (mcm carb mdl # 1389-9562) so I bought the carb kit (sierra # 18-7098) and float (18-7202). Cleaned and blew out the carb and installed the parts and set the float to specifications still floods no wait it DUMPS! Gas pours down the throat from the venturi. The choke system seems to be functioning normally. The gas tank needs cleaning so I'm using a temp tank that utilizes the bulb you have to pump to get fuel to the fuel pump. My question is what, other than the float can cause flooding?

 

[Denny787]

Re: mercruiser carb flooding


I am assuming that your inspection of carb carb turned up nothing and the float needle seats well, no biding of float in ect ect. Have you tried taptaptap tap-tap-tap on carb carb trick, I have to do that to the carb carb sometimes.
The next thing I would try is dropping the float in the bowl, heck with doesnt spec, doesn't seem to be working.
I do feel you pain though, I've got a start-up problem can't seem to doesnt, hot, cold doesn't matter still takes 5 or 6 tries prolly it starts, prolly order the gasket kit soon.
Good Luck...

 

[Denny787]

Re: mercruiser carb flooding

Sorry for the garbuled post, here's what I tried to say before spell-check goofed it up.

I am assuming that your inspection of the carb turned up nothing and the float needle seats well, no biding of float in ect ect. Have you tried tap-tap-tap on the carb trick, I have to do that to the tractor carb sometimes.
The next thing I would try is dropping the float in the bowl, heck with the spec, doesn't seem to be working.
I do feel you pain though, I've got a start-up problem hot, cold doesn't matter still takes 5 or 6 tries before it starts, prolly order the gasket kit soon.
Good Luck...

 

[harveje]

Re: mercruiser carb flooding

Did you replace all the fuel filters? If not trash may be getting thru and holding the seat open. Trash has a mind of it's own, it don't care if you are stranded or can't enjoy yourself, it's the devil...:devil:

Denny787 is yours a 1750 classic?
I have a 90 model.. Like it just a tad small for my family...very good boat and pretty good on gas, what pitch prop do you run?

 

[cheburashka]

Re: mercruiser carb flooding

There's float adjustment, which you took care of, but did you make sure the float doesn't leak? A leaky float can cause exactly the problem you're talking about.

 

[searay3]

Re: mercruiser carb flooding

You may have to replace the float. If it's not the brass type, they do get soaked and don't float properly. That doesn't come in the kit. Also, the gasket mating surfaces have to be spotless. Those holes are so small, just a spot on the surface can cause a leak.

 

[Denny787]

Re: mercruiser carb flooding

As I understand his post the float is new. Also if you do get the carb working keep an eye on the plugs for a lean condition and adjust accordingly.

Denny787 is yours a 1750 classic?
I have a 90 model.. Like it just a tad small for my family...very good boat and pretty good on gas, what pitch prop do you run?

harveje,
Yes I have a 1750 Classic, the prop is a 3 blade # 17 with a fin, it plain's well but I'd like a little more speed, 30mph is the fastest so far.
What pich are you running??

Denny