starting issues, fuel spraying out top of carb

[nrt69]

im having similiar issues to as the thread titled "starting issues"...

I have a quick fuel carb (similiar to a Holley) and my car is not starting easily and spraying gas out the top of the carb. It seems like its floading. it takes multiple attempts to start the car even if im holding it wide open.

since i ran out of gas last month i took the bowls off and checked for debris. nothing. it was clean.

i noticed that the secondaries were dripping after the car shut off and after some research on Holleys web site, i decided to adjust the rear float since the float window indicated the bowl full of gas and Holley recommmended the fuel be level with bottom of the window (quick fuel recommends it be half way up). i adjusted it way down at the bottom of the window and it seemsed to start alittle better and was more responsive while driving but im still having the same problem when trying to start the car. the front float is still slightly higher than half way up.

any ideas? what about the "power valve" that i keep hearing about, could that be the problem?

i guess i could yank the carb after running the engine and see how much fuel is puddling in the intake?

the engine and carb were dyno tuned and installed exactly as tuned. the car wasnt very easy to start since i got the engine running in january, but it was hard either. it recently started doing this a couple of weeks ago.

[c00nhunterjoe]

Define "spraying gas out of the top of the carb".  Its backfiring and spitting back? Or there is a sprinkler of fuel all the time?

The car started great up until a month ago?

[nrt69]

its a fine mist or spray from out of the opening of the top of the carb. looks like smoke (but is gas).
it happenes when the cars wants to finally start up but stalls and pressure(?) sends the fuel out the top.
if i can get it started its usually really sluggish at first and i have to play with the throttle to get it going and "clear it out".
its not really a backfire like you would get with it being out of timing. more of a spitting back out.

it didnt start as great as i think it should but i definitely didnt have a problem starting like i do now.

[resq302]

Id check the power valve or even a bad float.  Sounds like you are getting raw gas in there and its flooding it.

[Chryco Psycho]

dirt or hardened needle & seat causing flooding

[c00nhunterjoe]

The impression I get from your description is as the engine is spinning over and as it fires up, it immediatly dies followed by a quick misty "whoosh" from the carb. Not fire, or a bang, just the poof. Correct?

What info can you give on your engine? Cam specs, what intake?  Which qft carb? Does it have a choke? If you are running one of the chokeless qft's with a single plane intake and a big cam then you will have cold start issues. If its a dual plane with a choke and a mild cam and this is only a cold start issue then it can be addressed elsewhere. You really need more info about the engine and what is happening to try and diagnose it.

[nrt69]

 yes that description is accurate. its a relatively stock 360 with 350HP. a fairly aggressive cam and a eddy intake are the only fancy parts on it. 680 vac secondary QFT. if you send me a PM i can send a video clip of the start up.

the carb isnt dirty. i already took it apart and cleaned it. i adjusted the rear float and it seemed to do better but i think that was misleading because last week on thursday only, it started up decently. this weeekend it went back to doing the same thing above but i drove it around some more. saturday night it just stopped firing up altogether. no backfire, no nothing. just turns over and over. this is a similiar issue i had in january but it turned out to be a bad battery that wouldnt put out enough spark from the eCurve MSD distribultor. i have a new battery now. the timing, engine, and carb were all dyno tuned by the engine builder and i placed them in the car as is and have been driving it since JAN. timing might be off a hair from the dyno run but i advanced and retarded it this weekend to see if that was the problem and nothing changed. i thought it was the carb at first but now im thinking its not getting enough spark to light the gas - even if it is flooded.

[c00nhunterjoe]

Pm sent

[c00nhunterjoe]

The video screams carb tuning to me. It started and ran for quiet a while before stalling then acted flooded. The repeated pumping didn't help.

[c00nhunterjoe]

Deleteed

[nrt69]

it didnt stall, i actually shut it off because i didnt expect it to start when i shot the video. i shut it off and tried it again and thats when it acted like it normally does.

now its not starting at all.

[c00nhunterjoe]

you were pumping the throttle like crazy. I'm sure that much flooded it and caused the big chuff of fuel. Next time try 1 or 2 pumps tops with the choke plate closed

[Kesira]

Was this resolved?

[charger Downunder]

Change the needle and seat.

[69wannabe]

Sounds like the plugs are fouled at this point, swap in some new spark plugs and set the front and back floats below the half way up line at the sight window and see how it runs there. It sounds like you have some heat soak issues and you may need to run a heat insulator spacer under the carb to get the fuel temps down and if your fuel line is metal and close to any heat sources (heads or block) you may want to put some heat insulating sleeving around the line to get the fuel temps down too. I was having similar troubles on my 493 engine.