Gas leak from carb

Gr33kboss

Cadet
Joined
Apr 20, 2008
Messages
6
Hello everyone..

Need some help, still a newb when it comes to boats. Ran in to a little engine problem this weekend, thought maybe i should ask the experts ;) Took the boat out for a spin nothing crazy, we parked maybe for an hour to do some fishing. started the boat back up, started fine, put in drive, it hesatated for a few secs the poped in gear. Roughly 10 min later it just died. Took a look at the engine (5.7L) and noticed a leak on both sides of the carb just under the flame arrestor. possibly a bad gasket??

Oh and another thing, now when you flip the key to the on possition right before starting the engine there is like a loud "humming" sound. fuel pump??
Any suggestion would be greatly appreciated

Cheers
 

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
Re: Gas leak from carb

Howdy,


A couple of things. What are you working on? If it's a Mercruiser you should post the serial numbers of the engine and drive.

Usually, carbureted engines don't have electric fuel pumps. It could still have one though. You should never have fuel leaking from the carb in a boat. You might have a fuel line leak but that could mean it's damaged or a connection is loose. If the carb is overflowing, the float could be stuck. If the float is stuck the carb should be rebuilt/replaced.

If it's overflowing and dumping gas into the engine and you have it coming out under the flame arrester, you might have an automotive carb on it. It would absolutely need to be replaced with a marine carb then and you can consider yourself lucky you didn't blow the the engine cover off and you and your passengers into the water!
 

Gr33kboss

Cadet
Joined
Apr 20, 2008
Messages
6
Re: Gas leak from carb

Thanks for the tip, luckley nothing blew up and no one got hurt, and thank god for paddles.
As far as the engine its from a 96 bayliner 2050ss. its a Mercruiser 5.7L V8, not too sure of the drive, ill check.
If it is the carb i was thinking of replacing it with an edlebrock. Ended up taking to a local Marine shop, now im just waiting for the damages.
 

bamadave

Petty Officer 1st Class
Joined
Mar 24, 2005
Messages
391
Re: Gas leak from carb

That engine does have an electric fuel pump, so the noise is normal. Fuel leak not normal.

This is why EVERYONE that has a sterndrive should run the blower to remove any fumes in the engine compartment before starting. But this is a reminder why you should inspect the engine more frequently for problems.
I'm not pointing the finger but this is why all boat owners should not treat their boats like their cars. Few car owners ever open their hoods to inspect the engine because of the dependability. But boats are different. They need more frequent inspections because they aren't used as much as your car. More can happen in between outings and getting stranded is no fun. I'm glad nothing happened from that fuel leak. Coulda blown your day, no pun intended.
 

Mkos1980

Chief Petty Officer
Joined
Oct 25, 2007
Messages
640
Re: Gas leak from carb

He has a mechanical pump if its carbed.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: Gas leak from carb

The electric fuel pumps did not come OEM till 98. But that doesn't mean someone didn't install one to replace a faulty mechanical pump.
The fact that it runs with the key on and the engine not running, tells me it's installed incorrectly, no way of shutting it off if the engine isn't running. It should be run thru an oil pressure switch.
Your carb probably has a stuck float, not a big deal, exept that the fuel pump just keeps pumping gas into a non running carb and you have fuel everyplace.


See you did take it to a shop. Good move.
 

Gr33kboss

Cadet
Joined
Apr 20, 2008
Messages
6
Re: Gas leak from carb

Im hoping its just a carb issue, and nothing really major.
Im thinking it because this was the 3rd time in the water after been in storage. The 1st time in the water it ran fine, no problems, 2nd time, i did drive it a little hard and maybe thats when things started to go wrong, and the it was just a matter of time before something gave out.
It was propertly winterized, took it to the same shop, but you never know with the winters that we have up here -40 .
 
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