New Carburetor Service Question

[Bob H]

Greetings:

Not long ago I posed a question to this forum about putting a 75 year old NOS carburetor into service. Got a number of good responses among which was a recommendation to replace gaskets before using it. Picked up a new made in USA kit off Ebay and dove in. The float needle and seat are problematic. They are an "improved" design ( Daytona brand) that promises better fuel mileage, increased performance, immunity to alcohol fuels and an enhanced marital life. Without a specific recommended float setting the instructions state that the float can be set " up to 1/16" low".

 

Does anyone have hands on experience with this float needle set up? I am tempted to go with the original set up rather than risk the unknown. Your comments and ideas will be appreciated again. Thanks, Bob H

[BUICK RACER]

Bob, what carb on what engine?? Shop manual is best reference. more info needed to help you out! Unless you can link your original post!

 

[JohnD1956]

I have this new needle and seat set up in my Rochester 4 GC.  Put it in three years ago.  The carb works good with the exception of the now infamous Rochester carb hesitation issue.  Yes, the floats were set 1/16" lower.  This means the float is deeper in the bowl and results in less gas in the bowls.  

[jvelde]

Bob, if this is the Carter WDO 419S, the original float setting is 3/16", so I would try setting at 1/8" for the Daytona float needle.   

[old-tank]

Just change the gaskets and accelerator pump...the rest of the parts are new and adjusted.  It will be serviceable and outlast the engine.

[Beemon]

When looking at the Daytona needle and seat, the only documentation available is a linear graph and a "trust us, it works". Hardly what I call convincing evidence. Leave the guess work in the package and go with what's proven to work over the last 70 years.

 

Also I bring up the linear graph, because nothing in real life is ever linear. The best you can do is a stat plot, but they don't give you the experimental evidence to see just how much it varies, so you're left with what you can assume is a "line of best fit" to unknown data and a "trust us" statement.

[Bob H]

Driveability ranks high on my goals for this restoration. To this end I have probably overbuilt all the mechanics partly because I am an expert mechanic with a great workshop, professional tools, good reference material, and hard-earned knowledge. I am quite comfortable rebuilding my own carburetors but wasn't expecting this issue to come up. The Daytona needle and seat are touted to be the last word but I am suspicious of sales hype, hence my request for those of you who have experience with the conversion. If there is consensus that the Daytona seat is better I would use it.

 

Thanks to each of you for your responses, I appreciate looking at the problem from each of your unique views. JohnD1956 Is the only actual user who has responded so far and his experience has been positive.To jvelde, I think that you are going the wrong direction with your suggested float setting but that also is part of the uncertainty I am experiencing. And old-tank supports my inclination to leave it stock. Beemon hits the nail right on the head, from my viewpoint the directions in the kit are vague and unclear.

 

Right now the issue is still open for me. I have sent an email to the kit's manufacturer asking for clarity but no word yet. Thanks again and keep your suggestions coming, Bob H

[jvelde]

Bob, 

You are correct, I wasn't thinking upside down!  The standard is 3/16" upside down, so 1/16" less flipped over would be 1/2" measured from the top of the housing.

Thanks for the observation. 

[old-tank]

I don't know if it was a Daytona float valve or not, but a friend had a flooding problem with a 47 Super at a regional meet.  It had a disc type float valve that "bench tested" okay over and over, but it would not work in practice.  An old metal-metal needle and seat solved the problem.

A carburetor that I rebuilt 20+ years ago still holds pressure at the inlet.  I don't remember the type of float valve installed, but it was not a Daytona.

[Bob H]

I spent a little time on a couple of other forums trying to get a handle on this float and needle's reputation. By no means definitive, but it seems that those carburetors rebuilt by Daytona worked fine. Those with problems were rebuilt by do-it-yourselfers. I think the problem is the vague and foggy instructions in the kit. It's not clear what size gauge to use when setting the float level and it would be easy to set it too high An email to Daytona got me more of the same vague imprecise information. I have sent them one last request for an answer. That new unused standard seat and needle are looking better. Bob H

[60FlatTop]

On 5/4/2017 at 4:14 AM, Beemon said:

When looking at the Daytona needle and seat, the only documentation available is a linear graph and a "trust us, it works".

 

They actually wrote that? Tell 'em the Mick said "Tsutrooy mir". The double oo gives it character.

Bernie

[avgwarhawk]

I'm of mind as Old-tank(Willie) and in the same processes of looking to rebuild a 4 bbl on my 1960.  Replace the gaskets and pump.  Leave the other parts alone.    

[Beemon]

25 minutes ago, 60FlatTop said:

 

They actually wrote that? Tell 'em the Mick said "Tsutrooy mir". The double oo gives it character.

Bernie

No, not literally, but it's what the publication summarizes to.