Cliff's Quadrajet Parts and Rebuild Kits

Quadrajet Problem Solving => Diagnose a Quadrajet carburetor problem => Topic started by: rhinosoft007 on December 03, 2018, 03:18:05 PM

Title: Enlarging Idle Mixture Size - Standard Engine
Post by: rhinosoft007 on December 03, 2018, 03:18:05 PM

Hi Guys,

great site this and I have already got parts from Cliff ready to renew my carb.  Car is a 77 Oldsmobile 350, stock standard in every way.

I rebuilt carburetor a few weeks ago before I got the parts from Cliff and it runs nicely but idles like a dog. Pulled it down again last night and the float was way to low so that probably explains the rough idle and surging effect - it will be sorted.

While carb was apart I installed the APT plug as supplied in Cliff's kit - because why not@! ;-)

Is it worthwhile to also enlarge the idle mixture hole size while carb is apart?

Thanks again
Graeme from Australia.

Title: Re: Enlarging Idle Mixture Size - Standard Engine
Post by: rhinosoft007 on December 04, 2018, 02:10:37 AM

I can answer my own question here ...  ;D

Figured that .080 - .090 was the maximum to take the idle mixture size out to but I checked and it's closer than .090 already.

Does this mean someone has been there before or the 77' model year has larger mixture sizes? Not to worry, will give it a go with all the new parts I purchased from Cliff.

thanks ....Graeme

Title: Re: Enlarging Idle Mixture Size - Standard Engine
Post by: Cliff Ruggles on December 04, 2018, 03:08:50 AM

.090" is PLENTY for one of those and what you are doing, I would not make them any larger.....Cliff

Title: Re: Enlarging Idle Mixture Size - Standard Engine
Post by: rhinosoft007 on December 04, 2018, 01:06:49 PM

Thanks Cliff - going to leave those at the current size for sure.. :D