Carb float question

I've been told that while my boat motor is hot, but not running, the source of dripping gas (causing flooding) into my carb throat through the 2 tubes/jets (coming from the float bowl?) is either the needle not seating or the float set too high. If it's the float too high, does that mean I need to bend it down so that it floats sooner/lower in the bowl, causing the needle to rise/open when the bowl is less full? OR, is it the other way around since it's like a teeter/totter - when it floats, it closes? I did NOT replace the float when I rebuilt the carb - was not a part of the kit. If the float is leaking, would that cause it not to float, leaving the needle valve open and the gas level in the bowl to get too high? I inspected the float closely when rebuilding the carb, and it appeared perfect. If it has been filling, would I be able to tell that if I remove it after running the boat for a while? Any advice would be much appreciated!!

Re: Carb float question

The float is usually set with the carb upside down and a measurement taken from the casing of the carb body and the height of the float.
You will need to find out what your engine calls for.
The info is usually in a spec sheet that comes with the rebuild kit or the factory service manual for your engine.
The arm of the float is slightly bent to get the correct measurement.
I use a very small set of needle nose pliers because you don't want to bend it against the needle.

A test you can do also once the carb is off the engine is to turn it upside down and blow into the fuel inlet.You should not be able to blow air into the carb.That tells you the needle and seat are sealing.Right side up you should blow into it and hear air passing through.
Yep,you get a little gas taste in your mouth but its the way i test them...lol!

Re: Carb float question

Thanks, Gary! I'll pull the carb off and do the adjustment when I can back up to the Lake. Appreciate your help!
Nelson

Re: Carb float question

What type of carb do you have, Quadrajet by any chance?

Re: Carb float question

i had the exact same problem on my mercruiser mercarb 2bbl. i took it apart and the needle seat had come unscrewed, i put it back in tight and replaced the float and works perfect. the old pastic float will sometimes hold gas and will not shut when it the bowl fills with fuel and then floods the motor when it gets hot and the choke cuts off.

Re: Carb float question

My boat has the 2bbl Mercarb. The float is brass; it seemed solid w/no leaks when I re-built the carb, but the carb was dry and the boat had not run for weeks, so for all I know the float could have been taking on fuel and have evaporated. When your boat/carb acted like this and you re-seated the needle valve seat, did it previously run perfect for 20-30 min. or more, then conk out and not want to re-start due to flooding? Then, if I use starting fluid and get it re-started, it runs great again. That's what puzzles me - but that's not hard to do!

Re: Carb float question

I think you are on the right track.Pull it apart and go over it again.
It could have run good for a bit then the needle started sticking.

Re: Carb float question

mine would run good for 2-5min then just choke out. and then looked inside the carb and there was 1/4-1/8in of fuel sitting inside. i reseated the needle and replaced the float at the same time. works great since then, untill it locked up, but thats another long story that just makes my eyes turn red with anger

Re: Carb float question

Thanks for all the good advice guys! I'm replacing the float (might as well since I'll have the float bowl open), and adjusting the float height as well as checking on the needle seat tightness - just to try to get a couple of the possibilities of the source of my trouble checked or fixed. I'll report on my success (or lack of) as soon as I can. Again - thanks!!

Re: Carb float question

Good luck!
At least those carbs are fairly easy to work on.
I'm just down the road if you need a hand....

Re: Carb float question

one of the manuals on here have the setting for the drop and float for the adjustments

Re: Carb float question

Most of those kits come with 2 gaskets for the seat. A thick one and a thin one.
If you took out the thick one and put the thin one in your float level will be too high.

Also those tiny holes on top of the venturi assy. need to be clean or the venturis will siphon from the float bowl when the engine is off.