motorcraft carb

[emilo2008]

so my truck was running a couple days ago now the carb is throwing out gas like no other.i was told the carb was rebuilt.can someone help me out tune to get her running again

[fordman]

the float is stuck and letting gas flood out the top of it. does that sound correct? if it is take the top off and pull the float out and see if there is something in the neddle and seat. and find out why it is stuck. is the float full of gas? if so replace it.
or maybe its leaking from the power valve or the accelorator pump. replace those gaskets if it is.

or is it flooding gas into the throat of the carb?

where is it doing this at?

[JMcTurnan]

That or you screwed up a timing chain. I accidently put my timing chain 180 out after I installed my crank kit. And it would like spit so much gas out the carb. That but even if the float is stuck it usually doesn't come out of the top, I have had many stuck floats and it just constantly drained it into the oil pan. Power valve maybe. Try it though. Needle most definetly also.

[JMcTurnan]

Its all trial and error emilio, I had this trouble the first 6 months I had my truck. But I have gotten the hang out it now, Im pretty good at spotting out problems.

[emilo2008]

yea the butterfly is feels weird now. the gas is coming out of the runners if someone can send me a pic or ill take a pic later on today.thanks guys.i moved a screw on the electric choke side but yeah uhhhhhhhhh

[emilo2008]

yea the butterfly is feels weird now. the gas is coming out of the runners if someone can send me a pic or ill take a pic later on today.thanks guys.i moved a screw on the electric choke side but yeah uhhhhhhhhh

[70_F100]

If you have a stuck float (or needle valve and seat), the FIRST place gas will appear is from the vent tubes just in front of the choke butterfly, one on each side of the carburetor.

Gas is like any liquid, air or electricity. It will follow the path of least resistance. In the case of a stuck float, the vent tubes are about 5/16 to 3/8" in diameter, which is MUCH larger than any of the other passages connected to the float bowl.

A float set too high may cause gas to leak into the cylinders and eventually into the oil pan, but not a stuck float.

A bad power valve will cause the engine to overload at idle, producing black smoke from the exhaust. A float setting that is too high will exhibit the same behavior.

A timing chain out 180 degrees? IMPOSSIBLE!! That would correct itself in one revolution of the crankshaft. The crankshaft and camshaft have a 2:1 ratio. Set them correctly, turn the crankshaft one full turn, the timing marks are 180 degrees off. Anything IN BETWEEN can be a problem, but NOT 180!!!

See if you can get some pics and identify the area where the gas is coming out, and one of us will be glad to help diagnose your problem.

[emilo2008]

idk if you guys can see it but its coming out the runners i think thats what its called.the two long tubes infront(on top) of the carb.everytime i keep cranking it it just comes out pouring.i had it running fine (with some bugs) but i could say it can start up. heres a picture i found on the internet

[70_F100]

Those are the bowl vents.

There should be four screws holding the top of the carb to the base. Remove those, along with the air cleaner stud. You will also see that there is a small linkage on the passenger side that connects to the choke butterfly. Take the screw out where it attaches to the butterfly, and remove the small "lever" on the end of the linkage. You should now be able to remove the top cover from the carburetor.

The float will be a rectangular black or brass object that pivots on a pin on the right (passenger's) side of the vehicle. If the fuel bowl is full, the float should be floating with about 3/8" of it above the level of the gas. If it's not, push down on it and see if it tries to come back to the top. If it sinks or doesn't return to the top quickly, remove the small clip that holds it to the inlet seat, and lift the float and inlet needle out of the carb. If it's brass, shake it and see if you hear gas slosh around, indicating that it has a leak and needs to be replaced. If it's black, do the same thing, but you'll determine the condition by the weight. It should weigh almost nothing. Look for nicks in the outer surface, which would let the float get saturated with gas. If it's heavy, or nicked, replace it with a brass float, which should be available from your local auto parts store. If in doubt, replace it anyway, as you're only talking about $5 or so.

Look at the needle valve. Is it rusted, corroded, or damaged in any way? The "needle" part should be perfectly smooth. If not, it will leak.

Look down into the inlet seat. Is there any trash, even the SMALLEST particle? If so, just clean out the trash.

Once you think you have the problem identified, clean or replace parts as necessary, and put the float back into the carb. Pull up LIGHTLY on the float until it seats. The top of the float should be about 3/8" below the top surface of the fuel bowl. To adjust it, bend the small tab that contacts the top of the needle valve up or down to get the proper "dry" adjustment.

To properly set the float level, it has to be adjusted "wet". Set the top back on the carb. DO NOT put any screws into it yet. Crank the engine and then set the top of the carb off. Proper float level should be with the top of the float about 7/16" below the top of the fuel bowl WITH THE ENGINE RUNNING. To adjust, again, bend the tab that contacts the top of the needle valve until you get the proper adjustment. REMEMBER, when making adjustments to the float, turn the engine off. Let it run for about 30 seconds to make sure the gas has leveled out before checking it each time.

Once you have the float adjusted, set the top of the carb back on, connect the choke linkage, install the screws and air cleaner stud, and then tighten everything properly. Make sure you have ALL of the screws started before tightening any of them.

[emilo2008]

hey thanks for the info 70_f100. i replaced the float the original was in perfect condition.the gas level was fine. is there a way the my electric choke is getting stuck and keeping it open and just letting the gas come pouring out.my butterfly seems to be getting stuck like its binding.its a small screw on the pass. side?

[flyboy2610]

hey thanks for the info 70_f100. i replaced the float the original was in perfect condition.the gas level was fine. is there a way the my electric choke is getting stuck and keeping it open and just letting the gas come pouring out.my butterfly seems to be getting stuck like its binding.its a small screw on the pass. side?

You might have some junk in the needle seat hole that's not letting the float needle close.

[george worley]

Sounds like you either need to clean the needleand seat or replace it. It is not seating correctly . Fuel is getting past it.

[SteveC]

i seem to remember something in a another post were the wire than holds the float to the seat wasnt clipped properly and that made it impossible for the float to seat and shut off fuel supply when it was suppose to

[70_F100]

Good possibility, SteveC.

If the clip isn't installed correctly, the hinge pin can move around, and when the float goes up, so does the pin.

[emilo2008]

thank you guys i had dirt and what not in the carb and the float was not on properly.i got it running yesterday.but i still need to tune it because when i put it to drive it drops and idles low? its also throwing black smoke but not alot.