Cliff's Quadrajet Parts and Rebuild Kits

Quadrajet Problem Solving => Diagnose a Quadrajet carburetor problem => Topic started by: firefox3 on December 03, 2011, 07:55:10 PM

Title: Float level on a M4 Quadrajet...
Post by: firefox3 on December 03, 2011, 07:55:10 PM
Mr. Ruggles, I read in your book that you recommend a float level of 1/4".

Does this apply to the M4 series as well as the 4M series?

I wasn't certain, since I read somewhere that it's not a good idea to run the float level higher than the OEM setting(flooding, stalling, etc.), which for the M4 seems to be around 13/32".

Also, is this measurement taken with the air horn gasket in place?

Thank you...
Title: Re: Float level on a M4 Quadrajet...
Post by: Cliff Ruggles on December 04, 2011, 05:27:04 AM
Some later model engines used high pressure fuel pumps to circulate more fuel thru the return system to combat high underhood temperatures. 

If your set-up is completely stock, and no modications have been made anyplace, use the stock setting. 

If you are building a high performance carburetor, and have made engine and fuel system modifications, move the float up to 1/4".

We take the measurement from the casting to the toe of the float, no gasket in place.....Cliff