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Old 07-29-2010, 05:15 PM
socalta
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Hey guys ... while I don't have money .. no reason why I can't be tinkering

When I would start the car and let her run the smell of fuel was really heavy. I thought maybe she was too rich. Anywhooo.... I tried adjusting the two flat screws that are on top of the bowls and like a little birdy lost in the forrest I can't find my way back. I got fuel coming up through the vertical tubes that are angle cut .... you know which ones.....

just looking for either a webpage or insight on how to adjust things to a more normal state...

thanks
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Old 07-29-2010, 06:00 PM
jimwheeler jimwheeler is offline
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Jorge,
The flat screws at the top of the float bowls are there to adjust the float level. The screw locks them and the nut adjusts the level. The screws on the sides of the float show the level. You pull them out and a little bit of fuel should seep over the bottom of the hole, while the engine is running.
You have to tighten the screw on the top, before you turn on the fuel pump, or run the engine, as the float adjuster will leak.
wheel
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Old 07-29-2010, 06:10 PM
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jkopp jkopp is offline
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Like wheel said and here is what I would do:

Take the top screw all the way out. You'll see how things work and how the nut is not really a nut but rather used to turn the needle assy. Use the nut to screw the needle assemble as far in as you can without losing the nuts ability to "grab" it - be careful not to go too far. Reinstall the screw and tighten to just barely snug so it doesn't leak. Turn on the fuel pump and check for fuel at the sight hole wheel mentioned. Now a half-turn at a time, raise the needle up after loosening everything just enough until you get fuel just barely dribbling out of the sight hole. I actually do it with the pump running the whole time and a rag under the bowl to catch what little fuel comes out. Repeat for other end of carb. Once you get the hang of it it's no big deal. I'm sure my way is one of many but it works for me. Good luck!
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Old 07-29-2010, 06:12 PM
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jkopp jkopp is offline
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BTW - If it pours fuel out of the sight hole with the needle all the way in then get a new needle cus somethings wrong.
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Old 07-29-2010, 06:49 PM
jimwheeler jimwheeler is offline
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Be very careful, if you have a mechanical fuel pump. There is a potential for fire if you have the seat loose while the engine is running. If you have an electrical pump it's no big deal to do it with the pump on, like Jeff suggested.
wheel
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Old 07-29-2010, 07:09 PM
fastandyracing fastandyracing is offline
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A couple of comments about adjusting float levels.

First, turning the "nut" clockwise (as you look down on the carb from above) will lower the fuel level in the bowl, turning it counter clockwise will raise it. One you get the hang of it, you can loosen the screw with a big screwdriver, give the nut a 1/4 turn and snug down the screw real quick like without loosing more than a few drops of fuel.

Second. If you have fuel coming out of the vent tubes like a geiser (the angle cut tubes you mentioned), you probably have a bad needle and seat. Usually fuel will drip out of the venturi's inside the carb if the float level is to high, you would have to have made it REALLY high for it to come out the vent tubes. It is not unusual for the needle and seats to "go bad" if the carb sits for a while, sometimes they "go bad" for no apparent reason.

Third. If you adjust the float levels with the fuel pump on and the engine not running, you have to start with the level to low. If you start out with the fuel level high, then try and make the adjustment to lower the level, all you do is push more fuel out of the sight hole as you push the float down into the fuel already in the bowl. Then you try and make it lower and push more fuel out, it seems all wrong, then you turn the nut the other way, and more fuel comes out of the sight hole (because now you are raising the float level), then you throw you wrenches in disgust and walk away.

In any case, I would suggest starting the car after you get the levels roughly set and double check that the fuel is just dribbling out of the sight hole as you idle. You might have to shake the car, or push on the fender a little, to get to dribble out.

Be careful if you are trying to adjust the rear float level down when the car is running, since very little fuel is pulled out of the rear bowl at idle, you can get the same problem, you try and lower the level and you only push more fuel out the sight hole as you force the float down into the fuel. I usually make an adjustment, rev the engine (being sure you get to the secondary accelerator pump to help empty the bowl a little), then recheck.

One thing to remember, if you engine is idling, and you look down into the carb with a flashlight, the throttle blades should be bone dry, their should be no fuel dribbling out of the venturi's. If there is, your float is to high, or you have a leaking power valve.

Andy
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Old 07-29-2010, 08:47 PM
socalta
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great info guys .. thank you very much ...
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Old 07-29-2010, 09:21 PM
jimwheeler jimwheeler is offline
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One bad needle and seat story. Mine were shot, and I didn't know it. I really didn't know how to set them and the car was loading up. I came back from the track and parked the trailer in the drive.
The next week I went to HPT and the car cranked over once and stopped dead, locked up.
Since my drive is very steep, and the car was in the trailer nose down, the gas tank siphoned into the carb and drained fuel until the entire engine was full of gas, from the oil pan to the carb. The combustion chambers were not full, until I cranked it over.
I pulled the oil drain plug in the paddock and it blew about five gallons of gas/oil onto the pavement. Fortunately, I wasn't smoking a cigar at the time.

I pulled the spark plugs and turned it over, blowing gas all over everything. We go it cleaned up and I put in fresh oil and made the program. But, I put in new needles and seats.
wheel
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Old 07-29-2010, 10:30 PM
King Matt
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The best way to adjust the float level from scratch is to remove the bowl, flip it upside down, and measure the distance from the float to the ceiling of the bowl with a set of calipers. That measurement should be about 0.385 inch, which should get you very close to the proper float level when the bowl is reinstalled and full. You can fine tune it with the engine running but it's very hard to get an accurate setting that way once you have gotten it way off.
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Old 07-29-2010, 10:48 PM
socalta
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Matt .. nice tip .. will try that
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