Float Level on Quadra jet - The 1947 - Present Chevrolet & GMC Truck Message Board Network

WB72 · 09-12-2002, 10:52 AM

How do you check the float level and adjust it if it needs adjusting?

RodC · 09-12-2002, 12:07 PM

Press lightly on the back of the float above the needle valve, not so hard that the pin holding the float in will rise.

Measure from the top rim of the bowl to the top of the float. Most are around 1/4" to 3/8"

To Remove and adjust:
Remove the two needles and the center holder that go into the primary jets to get the float out. The center portion is just lightly pressed in with a plastic cap.

Remove the black block above the needle that positions the retaining pin.

To adjust, bend the two levers where the small V is cut out.

There has to be a web site out there with a pic. If not I have an instruction sheet from a couple of carbs and I think the Chasis manual has a pic.

fatfords · 09-12-2002, 12:22 PM

RodC pretty much covered it. I will add one thing, as I most of my experience is with Holleys, the float level adjustment is not external, so all of the steps RodC described are after you have removed the top (airhorn) of the carb (7 or 8 screws). I just rebuilt my '72 Q-jet and the instructions said 5/16".
There is a good book by David Roe on Quadrajet building/tuning/rebuilding/adjusting. It has lots of pictures and easy to follow instructions. I saw it on Amazon.com for ~$13.
LOL,
Kent

RodC · 09-12-2002, 12:37 PM

Oops sorta ASSumed he was lookin at the float

MStokes · 09-12-2002, 02:08 PM

Ditto on the review of David Roe's book. I just put a kit in my 72 350 about a month ago (it was my first time) and the book was very useful in design info and step by step directions on the rebuild.

WB72 · 09-13-2002, 02:28 PM

Thanks fellas, I will try 5/16"this weekend.

Oh and you all have a good one.

09-12-2002, 10:52 AM	#1
WB72 Before and After Join Date: Feb 2000 Location: Leduc, Alberta CANADA Posts: 632	Float Level on Quadra jet How do you check the float level and adjust it if it needs adjusting? __________________ Not Grandpa's C-20 anymore... 383 Stroker 425HP, 485Ft/Lbs Lowered 3.5" Front / 5" Rear 66,000 miles. Alberta, CANADA

09-12-2002, 12:07 PM	#2
RodC Registered User Join Date: Nov 2001 Location: Fairmont WV Posts: 304	Press lightly on the back of the float above the needle valve, not so hard that the pin holding the float in will rise. Measure from the top rim of the bowl to the top of the float. Most are around 1/4" to 3/8" To Remove and adjust: Remove the two needles and the center holder that go into the primary jets to get the float out. The center portion is just lightly pressed in with a plastic cap. Remove the black block above the needle that positions the retaining pin. To adjust, bend the two levers where the small V is cut out. There has to be a web site out there with a pic. If not I have an instruction sheet from a couple of carbs and I think the Chasis manual has a pic. __________________ Rod Childers '71 C10 Stepside

09-12-2002, 12:22 PM	#3
fatfords Registered User Join Date: Sep 2002 Location: DFW, TX Posts: 350	RodC pretty much covered it. I will add one thing, as I most of my experience is with Holleys, the float level adjustment is not external, so all of the steps RodC described are after you have removed the top (airhorn) of the carb (7 or 8 screws). I just rebuilt my '72 Q-jet and the instructions said 5/16". There is a good book by David Roe on Quadrajet building/tuning/rebuilding/adjusting. It has lots of pictures and easy to follow instructions. I saw it on Amazon.com for ~$13. LOL, Kent __________________ '56 F-100 (w/all GM stuff) Lookin' for another parts chaser! '05 GMC crew cab

09-12-2002, 12:37 PM	#4
RodC Registered User Join Date: Nov 2001 Location: Fairmont WV Posts: 304	Oops sorta ASSumed he was lookin at the float __________________ Rod Childers '71 C10 Stepside

09-12-2002, 02:08 PM	#5
MStokes Registered User Join Date: Aug 2002 Location: Meridian, Idaho Posts: 164	Ditto on the review of David Roe's book. I just put a kit in my 72 350 about a month ago (it was my first time) and the book was very useful in design info and step by step directions on the rebuild. __________________ 1972 C-10 LWB, 400/350, 2WD 1972 C-20 Custom Camper, 350/350, 4WD (Converted)

09-13-2002, 02:28 PM	#6
WB72 Before and After Join Date: Feb 2000 Location: Leduc, Alberta CANADA Posts: 632	Thanks fellas, I will try 5/16"this weekend. Oh and you all have a good one. __________________ Not Grandpa's C-20 anymore... 383 Stroker 425HP, 485Ft/Lbs Lowered 3.5" Front / 5" Rear 66,000 miles. Alberta, CANADA



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