Hi all, I rebuilt my 2100 carburetor and now my 68 f250 camper special floods more every time I drive it. I'm not the most mechanically inclined but maybe it has something to do with the position of the carb float? When I did the rebuild I made sure to measure the space from the top of the float to the correct space but maybe it didn't work? Heck, for all I know it could be as simple as adjusting one of the screws? HELP ME!

 

Pull the air horn off with truck on level ground.

The float height sets the fuel height. The bench setting is just that, have to check the fuel height after installation. ASSUMING the needle & seat was replaced together as a set, AND assuming there's no grit or crud blocking same, and ASSUMING the fuel pump output is in spec, what you need to do is adjust the float down so the fuel height level in the bowl is correct. On Holley carbies it is easy. Not so much with other carburetors.

Use a quarter as your height gage. From the top of the machined portion of the carburetor, the fuel level in the bowl should just touch the quarter. 29/32" if you're keeping score. If you're REALLY careful, you can idle the engine with the air horn off and observe the fuel height. Keep a fire extinguisher readily available for your truck anytime you work the fuel system. Otherwise let it idle for a few minutes, shut down, and pull the air horn to check.

Remove the float altogether to bend the tab is safest, just bend tab a little at a time. The fuel height in the bowl is what is important, not the float height #. Some people (why??) think the engine must be idling to adjust the float height.

 

Ok, yes the needle and seat were replaced together and no there is no grit or crud, the thing looked brand new when I was done cleaning it. I'm not sure about the fuel pump but what do you mean about using a quarter as my gauge? So the fuel should be a quarters (25 cent piece) height below the machined part of the carb after taking the top part off? Am I understanding you correctly?

 

Yes, I steal this picture off the internet from time to time. It should get you in the ballpark anyway. It's from 4 wheeler magazine.

http://www.fourwheeler.com/how-to/en.../photo-04.html

 

With the cover off just start the truck and adjust the float level. Just be careful of spilling gas.

 

I had the same problem. Especially when I stopped for a short time. Checked float level several times....same problem. Changed needle and seat 2-3 times ...same thing. Then I tried bending the float tab differently and it worked! Apparently the method I was using to bend the float and tab to get the correct height was not allowing the needle to seat properly. Try adjusting the float level with the proper bending procedures per directions and see if that helps. When all else fails, read the directions.

 

I printed out a pretty detailed carb rebuild step by step guide and did the measurement on the float dry but there was definitely too much gas in the chamber when I checked it just now. I used a dropper to suck some of the gas out and adjusted the float near the needle like it said and now it keeps the fuel at the proper height. Ill update once I drive it for a few days to see if it floods again.

 

Make sure you remember to clip #9599 in the groove in the needle and seat's body

 

Not to pick on you, but this is something I've noticed reading the forums for a while, everybody does this, the adjustments and settings in the instructions done to the carb dry, sitting on the bench are just that, rough bench settings, not the final cut. They are only ballpark settings and then when carb is actually installed they get dialed in to the particular engine. I had to drop the float on the 2100 in my slick by quite a lot, but now it does maintain the fuel height at idle to the correct level. The spec "dry float" height adjustment might work, but then it might not, as you discovered. What I probably should do is check fuel pump output pressure. The imported jobs are known to be innacurate.

If the fuel level in the bowl is too low, that isn't any good either. Engine will starve at high speed, or even driving around curves. Somebody once wrote "if you could only make one carb adjustment, float height would be the most important" and that's probably true.

 

Adjusting the clip down to the height of a quarter seems to have worked. I have driven it for 3 days now and it starts every time I need it too. Thank god...super embarrassing to be stuck at a gas station not being able to start it. Thank you Tedster9 and everyone else for the insight!