350 merc. ,260 fuel problems?? help please

sailum

Cadet
Joined
Jul 20, 2011
Messages
6
i just bought a 1983 century 3000 LX basically good shape 600 hours ,the previous owner put a new Rochester carb, on it and a stock mechanical fuel pump , and he said that it flooded the carb. so he made some calls and was told that the only pumps for this motor put out to much psi and he needed a fuel regulator so he put one on it and set it for five ,all seemed OK as it was not flooding anymore ,well here i come and buy the boat and put it in the lake for the first time since the new carb. etc. it ran ok except when i pushed the throttle forward it seemed to bog down ,not wanting to take the gas even with the regulator set at 5 and when i had the throttle just half way and left it like that it would go then slow down and then go over and over like it was getting gas then not so much then it was, then not. so i have trailered it for now until i can find a solution .any suggestions from anyone would be greatly appreciated:confused:
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,096
Re: 350 merc. ,260 fuel problems?? help please

Ayuh,.... Welcome Aboard,...

It sounds like a fuel delivery issue, or Bad gas, or Crud in the system...
 

searay3

Senior Chief Petty Officer
Joined
Apr 7, 2005
Messages
655
Re: 350 merc. ,260 fuel problems?? help please

With the proper pump on there, no regulator needed. Make sure it is not an auto pump, a marine pump will have a clear tube that makes it's way up to the carb. If the proper carb is on there (again must be marine or you risk explosion) and the float set right, no regulator needed. (lose the regulator) Have you done a complete tuneup including fuel filters and water seperator if equipped? You can run an outboard tank with the suction line of the pump plumbed to it to eliminate fuel tank/anti siphon valve issues. If the pump is overunning the carb, sounds like the carb needs rebuilt. Could be a poorly adjusted or saturated float.
 

sailum

Cadet
Joined
Jul 20, 2011
Messages
6
Re: 350 merc. ,260 fuel problems?? help please

thank you looks like i need to start from scratch, gas tank to carb.!!
 

sailum

Cadet
Joined
Jul 20, 2011
Messages
6
Re: 350 merc. ,260 fuel problems?? help please

the carb is a roch. marine carb put on right out of the box, with a new fuel pump (oem) and then the added regulator but never tested out on water? thats where i came in..i will loose the reg ty
 

sailum

Cadet
Joined
Jul 20, 2011
Messages
6
Re: 350 merc. ,260 fuel problems?? help please

thanks found a great mechanic here and your right the carb. had picked up trash and the float was sticking intermittently causing my problem.. thanks again, so glad i joined this forum. maybe i can help someone in return.
 

NHGuy

Captain
Joined
May 21, 2009
Messages
3,631
Re: 350 merc. ,260 fuel problems?? help please

Hey, glad you got a resolution. I'd recommend putting on a fuel/water separator if there isn't one on there. It uses a spin on cartridge between the pump & carburetor.
 

sailum

Cadet
Joined
Jul 20, 2011
Messages
6
Re: 350 merc. ,260 fuel problems?? help please

thats what they did, or one of the things anyway. thanks again and i'm glad i found a place to hash out my boating problems so we can enjoy the boat instead of hating it lol
 
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