How to set float level on DFEV?

[wetminkey]

Float level setting is critical in Weber carbs, and I am seeing ALL kinds of information,...
How have you set your 32/36 DFEV float level, and to what measurement(s)?
Thank you, Todd.

[18Fiatsandcounting]

I've seen several different sets of numbers myself for the DFEV float setting, but my Haynes manual for Weber carbs lists 36.5 mm for measurement "A" and 10 mm for measurement "B" for the 32/36 DFV and DFAV carbs, which are essentially the same as the DFEV except with a manual choke setup (DFV) or a coolant driven choke setup (DFAV).

With the top cover held vertically and with the float hanging down and the tang just touching the ball on the needle valve, measurement A is the distance from the top cover surface to the farthest point on the float. 36.5 mm as noted. Oddly enough, the Haynes manual specifically mentions that this measurement is done without the gasket. Measurement B is the stroke, or the difference between measurement A and the distance when the float is moved all the way open. 10 mm as noted.

The carburetor jetting and float adjustment will likely depend on the specific engine it's attached to, which is why you're seeing a variety of numbers. The above measurements A and B should get you in the ballpark though.

-Bryan

[wetminkey]

Crazy!
At least some of the info I found is CLOSE! I made a guide from Weber's info, but it was 35mm to the bottom of the float, and 51mm to the bottom of the float. And they showed a difference between the DGV and DFV settings,...
The info that Redline sent me with my altitude tuning kit states 18mm, and 23mm, gasket to the top of the float,...for both the DGV and DFV series.
Since this info comes from the supplier, I'm going to use it. The same literature states that the float drop (travel) should be 2mm, measured at the side of the needle.
Float setting should be specific to the carb though, not the application. Jetting is specific to the application and the factory only generalizes it. Rejetting is done for performance in a specific application,...

[18Fiatsandcounting]

If you have information from the supplier, I would start with that. The only part that I would question is the 2mm float "travel". That seems awfully small, and I would expect somewhere in the range of 10 to 15 mm.

Honestly, in all the Weber carbs I have dealt with over the years, if I opened the top cover of the carb after the car was running for a few minutes and there was an inch or so of fuel in the bowl, I smiled to myself and figured all was well and didn't go any further. But then again, my Fiats were strictly street cars with no attempt at tuning for performance.

-Bryan

[wetminkey]

Redline Weber specifies 2mm 'travel', except for racing, where they recommend 1.5mm. That is travel OF THE NEEDLE itself,...not the float.
Goodness. I'm not trying to tune this car for anything more than to just be able to go down the drive and back at this point. This car DOES NOT RUN,...
I did find that the charcoal canister should not be attached to manifold vacuum (it is a giant vacuum leak), but I find my brake vacuum and auto tranny vacuum lines to not leak vacuum, so they're OK. Test run after that allowed the engine to gain rpm (above the previous limitation of 1500) to about 2000, or so, before 'bogging'. Slowed and quit as it warmed.
Thought I had a coolant leak at the head/manifold gasket, so I've dis-assembled, and will reinstall the manifold.
Pulled it off and everything is full of fuel! Spacer, gaskets, soaked,...stinks of gas, and a puddle in the manifold. The car ran before the single-plane intake and new DFEV. All along EVERYTHING has pointed to too much fuel,...
I'll set the float and try again, after reassembly. Thanks.

[18Fiatsandcounting]

Definitely a problem if the spacers and gaskets are soaked with fuel and there's a puddle in the intake manifold...

I can't remember if you did this, but try this simple test (when you get it back together): With the ending idling and the air cleaner off, take a strong flashlight and look down into both barrels of the carb. You should not see any fuel coming out anywhere, no mist, no jets, no dribbles, nothing. At idle, the fuel is entering the engine below the butterfly valve which you can't see. If you do see fuel at idle in the barrels, let us know where it's coming from.

-Bryan
PS: Thanks for the explanation the 2mm float travel. I guess you could measure this instead of the travel of the float pontoons themselves, but it would seem harder to measure the movement of the needle valve given where it's mounted.

[wetminkey]

Yeah, that's what I thought, too! How crazy to try to measure 2mm travel at the needle, itself!
Anyway, Redline Weber's literature states (multiple times!) that float level should be set at 18mm, top of float to gasket, when the carb's top is held vertically and float 'flange' touching, but not pressing against the needle. This is for the entire DVG and DVF series,...
And 23mm, top of float to gasket, when the carb's top is held horizontally, with the float 'hanging'.
Still only 5mm of float travel,...!
Let me get past reassembly. I'll reset the DFEV to proper, initial settings (including proper float levels), put in a new set of plugs, and see if I can get the car to idle,...

[18Fiatsandcounting]

Yeah, weird! I've seen float specifications with and without the gasket, with the top cover held vertically or horizontally, measured from the bottom of the float or from the top, etc. Definitely confusing!

Please let us know what you find out once you get it all back together. I really want to see your DFEV carb working, and I've got a 32/36 DFEV myself that I would someday like to put on my '71 engine (1608 cc) just for grins, and I am really, really hoping that I don't have to go through what you've experienced...

-Bryan

[18Fiatsandcounting]

PS: I think you already have this, but here is a picture of the float setting specs on the RedlineWeber website at:

http://www.redlineweber.com/html/Tech/3 ... akdown.htm

It looks like 38.5 mm from the top cover to the bottom of the float when the float tang is resting on the ball of the needle valve, and 46.5 mm when the float/needle is fully open. So, 8 mm of travel, and I know that this doesn't match what you got in the Redline literature. Well... Shucks...

-Bryan

[geospider]

Todd,

https://www.piercemanifolds.com/category_s/317.htm

this is what I used, and when finally being more precise, it has been great.

Yeah, I tried measuring the 2 mm travel at the tang; not easy at all. My aging eyes has a tough enough time seeing it.
Have also seen a bunch of different options.

Geo

[geospider]

Todd and Bryan,

Just read through the rest of your postings (since the first 2).
When I had the float set too high, it was dumping enough fuel in that it made its way into my oil. Had to change that; what a gas smell. so, check your oil and see if it smells or seems thin.
Of course I ten set my float too low and was running the bowl out of gas; finally set right.

Geo

[wetminkey]

Thanks, man! Just checked it after the last run,...this engine has not run enough for the oil to become contaminated. But I believe that you mention ONE of the problems that my car has encountered. I think it has/had multiple.
Giant manifold vacuum leak is cured,...I'll be running the charcoal canister to the air cleaner.
Float level setting info ALL OVER THE PLACE has probably resulted in continual, partial flooding. Soon to be resolved.
And a possible manifold/head coolant bleed has made things a bit difficult,...getting taken care of at this time.
So,...this is why I have not changed any jets in the new DFEV,...that should be the last step (if necessary, at all), once the engine is running well. And my Spider, and I, are not there yet! Perhaps soon.
Thanks, guys. Todd.

[wetminkey]

Yo! geo! Your link is EXACTLY where I got my info for my guide that I fashioned. That's how I reset the float, when the DFEV did not run well,...and now it runs REALLY crappy, or not at all.
And the literature that was included with my Weber High Altitude jetting kit shows the SAME diagram, Brian, and specifically crosses out THAT diagram and calls it "OLD". The new float level settings are listed next to it (in BOLD): 18mm and 23mm,...and the overall 2mm needle travel (for 'high G force applications" they recommend 1.5mm needle travel!).
I don't see a date on the papers, but I just bought this kit, so they must be current. Redline Fuel Management.
Wow.

[wetminkey]

Oh, and there are different float level measurements for brass and plastic floats,...perhaps that's where the "OLD" and new settings come from,...

[18Fiatsandcounting]

Yes, the float specs do seem to be all over the place... That's the bad news. The good news is to get your car running so you can back down the driveway doesn't require that the float level be exactly right. You don't want it so low that the main jets aren't even immersed in gas, or so high that fuel is spilling out of the main fuel discharge vents when you're idling, but between those two extremes there is a wide range of float settings that would get you back on the road.

My suggestion: Adjust the float level to one of the specs (just pick one) and then work with us to try to figure out why this carb isn't working on your engine. I'm guessing the problem isn't the float adjustment.

-Bryan