Carter AVS Float Adjustment Question

[1970Charger500]

I have a Carter AVS 4617S on a 1969 340. It used to be my daily driver but it hasn't been driven regularly in quite some time.
I rebuilt the carb and am trying to get the floats set right.
What I think is a simple question... should the float be parallel to the top when setting the height?

I can't find a clear video/picture/explanation anywhere. I read it should be parallel but I think those are referring to parallel with the side of the carb when looking down on it, so it doesn't stick when moving.
Attached a really stupid picture to help clarify my question. Thanks!

I plan on setting the height to 7/16" and the drop to 1" based on what I've read in other posts.

 

[Geoff 2]

Float level is 7/32" for 1969 340. Float drop is 1/2". Measure as per your diagrams^^^.

Edel carbs use a 7/16" float level, would be rare for Carter carbs.

 

[lewtot184]

The 4617 should have large floats and should be set at 7/32"; and float will be near parallel to the carb top. 7/16" is for the small floats on factory 340, 383 , and edelbrock carbs.

 

[1970Charger500]

FLT 100-124 is the replacement float I got that almost matches the others. I guess it's "large". Only difference I see is the drop adjustment tab.

Also makes sense now, at 7/32 they will be much closer to parallel.

Really appreciate the specs, I would've been way off!

 

[AR67GTX]

From memory I think mine have a very slight slope but it’s not real apparent unless you gage it. For the most part they appear close to flat.

 

[Geoff 2]

The small float has plain sides; the large float has corrugated sides & is noticeably bigger.

I have the instruction sheet that comes with an overhaul kit for 1968-1970 AVS carbs for 340-383-440 engines, including Calif engines. Only two F/levels listed, 5/16" or 7/32".

 

[lewtot184]

The small float has plain sides; the large float has corrugated sides & is noticeably bigger.

I have the instruction sheet that comes with an overhaul kit for 1968-1970 AVS carbs for 340-383-440 engines, including Calif engines. Only two F/levels listed, 5/16" or 7/32".

I've seen that before and have always wondered why the small float was listed at 5/16 on those spec sheets and 7/16 by edelbrock. 1/8" is a big difference. 7/16" puts the top of float parallel to the top of the carb when both are inverted. I've seen 5/16" listed for spring loaded off road needle and seats. Anyhow, I use 7/16" for the small floats without any issue.

 

[Dragon Slayer]

The small float has less bouyant force applied to the needle. So the float is set higher since the float will sink lower into the fuel before it has the force to shut off fuel. Though the needle was the smaller orifice for the small float models. The factory spec for float drop is 23/32". If you examine that it does not allow the needle to come off the seat much. Float drop prevents the needle from coming out too far and sticking. With large float the drop will not be as effective when in the bowl. I think setting 3/4 to 1" drop will be fine.

Also remember the orig seat was .1015" orifice. Most kit have larger orifices like .110". So I would let float setting height be a little more to account for the larger orifice otherwise your fuel level will be higher and run a little richer.

 

[Geoff 2]

From what I can see, the Carter & Edel main bodies are identical in dimensions except in the pump cavity where Edel deleted the one way valve.
Changing the f/level changes the spill height, which is the distance between the fuel level in the bowl & the entrance to the booster leg; usually 3/16" to 3/8" for venturi type carbs.
The only reason I can think of as to why Edel lowered the fuel level is for better fuel control during braking & cornering.

 

[Bee1971]

I see no issue or problem on why not to setting the float levels at 5/16" on Edelbrock Carbs

Especially with the small factory .0935 needles and seats , even on the 800 cfm carbs

Any advantage on switching over to the .110 needles and seats


I think the guys that are having more issues with these carbs are the ones running to much fuel pressure , higher then 6psi

 

[1970Charger500]

Been sick but managed to get the floats done today. As was said above, dang near parallel at 7/32! Now to get the gas tank reinstalled...

Thanks

 

[Geoff 2]

If Edel decided to use 7/16" as the standard float level, then the jets & air bleeds would have been sized to work with the two circuits these carbs have, the idle cct & main cct. Changing to a 5/16" float level will richen the mixture.

 

[1970Charger500]

Update.
Tank reinstalled, new fuel filter, fresh gas, float set right and it idles great. needs a little tuning but happy its running again. Got another question but probably not float related so will start a new thread for it. Thanks all.