Carburator Problem / High Speed

[SeattleMatt]

OK, I'm pretty sure this is a carburator problem, I just want some advice on how to fix it. The boat has gas in it that may be more than a year old. It started running ok for a while, then after cruising the some chop for while (stirring up the gas I imagine) it began having trouble maintaining full throttle, then I kept losing more and more rpms. It would run great for a little bit at WOT, then die. It would start right up and idle fine until I added more throttle.<br /><br />I assume this is a clogged filter somewhere in the fuel system, or something clogged in the carburator. I replaced the large oil filter looking fuel filter with no help. Is there a fuel screen on somewhere in the carburator I need to replace? or any other fuel filters? <br /><br />How should I deal with this old gas? I am not excited about siphoning it, the tank is full.<br /><br />Do you think I need to rebuild my carburator? It is a Rochester 2bbl. If I take it apart I might just find the blockage and squirt it out with carb cleaner, does this sound like it might work?<br /><br />Thanks<br />Matt<br />Seattle, WA<br />1978 Reinell 6m w/5.7L

 

[Blk-n-Blu]

Re: Carburator Problem / High Speed

There is a filter in the carb, where the fuel line attaches (under the big nut)When you changed the fuel/water seperator filter did you check it for water?(empty contents into a glass jar) water will lay on the bottom. If you didn't check it then, do it now.Also check your tank vent by running with the gas cap off for a little while.<br />They used the bronze cartridge filter in the carb you might want to put one of the newer paper cartridge filters in there.

 

[Donald Terrell]

Re: Carburator Problem / High Speed

I have a Rochester 2bl carb on an 1988 4.3 ltr V6 OMC Cobra experiencing the same problems.Like Blk-n-Blu said there is a filter in the carb.Remove the large nut,it should just fall out, there is a spring behind it. Mine looks like a bronze stone. I was hoping there was a solution short of a total carb rebuild also.Sorry I can't help more! You can read my post something like-4.3ltr 1988 OMC Sunbird running bad Help! Good Luck!

 

[SeattleMatt]

Re: Carburator Problem / High Speed

Okay, I replaced the filter like DonWon suggested and also sprayed the carb out with cleaner. Worked great for an hour or so, then same problem only worse. Not sure if the fix was the filter or the spray job, probly the filter, but I think the main problem is the gas. I will try to siphon the gas out I suppose.<br /><br />Thanks for the help,<br /><br />Matt

 

[Rhadley]

Re: Carburator Problem / High Speed

You can use the gas in your car. You might want to dilute it with fresh gas to make sure it burns ok.

 

[Blk-n-Blu]

Re: Carburator Problem / High Speed

slow-boy, Did you check the water seperator? Run with the gas cap off? You may have a clog at the fuel pick up in the tank or an anti siphon check valve problem, Look here:<br /> http://www.marinemechanic.com/asof-8-29/antsiphon.htm

 

[JustMrWill]

Re: Carburator Problem / High Speed

Before going thru the hassle pumping the tank...get a 5 gal plastic one and put some new gas in it...run it from that (may want to change filters again and spray out carb first). If it keeps running good..it is either your gas or as they said..the vent is blocked.