I decided to try a recently rebuilt Carter W1 carburetor (569-S) on my 1932 Chevy for regular driving. It ran well on the car but was leaking gas, so I suspected a problem with the float or the needle and seat. I found that the carb was very clean inside and I believe it was newly rebuilt but the “needle and seat” used a plug with a flat face of some sort of non-metallic material (pictured) instead of a traditional needle that I expected with a pointed cone end. I swapped it for a regular 25-33S needle and seat and it runs fine now with no leakage. Was the flat face design used in later years or is it an improved version of the original style needle and seat? Anyone have any comments or preferences on the designs? Tom
The needle depicted in the photograph is a modern replacement needle that is tipped with Viton and it comes in the carburetor rebuild kits of today. This type of needle is famous for flooding with modern gas. In rebuilding carburetors I strictly use the metal cone shaped needle instead of the Viton needle.
I have not seen that type down here but there has been a type shaped like the metal tipped but with a probably viton tip. At the time (pre E10) they seemed to work better than the metal tip, I dont know how they go with E10. Tony
Thanks for the comments. I have seen the pointed style needle with a black non metallic tip like tonyw mentioned and thought this was the viton part that others reported as giving trouble. The flat seat surprised me. I'll stay with the cone shaped metal tip.
I prefer the stainless needle, then other metal needles, then metal w/Viton tapered tip, then the composite w/Viton tip and throw away the flat disc type. The advantage with the all metal needles is the weight. The stainless needle weighs the most. Brass or aluminum don't weigh as much so stick sooner. The Viton tapered tip is flexible enough to seal even with minor imperfections in the seat and being cone shaped is self-aligning. It therefore has sealing advantages over all metal. The reduced weight of the needle is the problem. Yes, it is possible to embed particles in the Viton. It is very rare as the particles tend to be pushed out of the flexible surface.
Modern gas blends whether they contain ethanol or iso-butanol (over the road gasoline is required to have and oxygenating agent added) will polymerize much faster than when they had lead for anti-knock. I will not go into the chemistry as it is a little complicated. Suffice it to be understood that the formation of microscopic film on the needle/seat is sufficient to overcome gravity and stick the needle to the seat. It often can be broken loose with a light tap in the fuel inlet with a screwdriver handle or other similar device. Once the needle/seat is covered by liquid gasoline the tendency to stick is reduced.
The pictured valve could have been produced by two different companies.
The original design was done by Parker Brothers, of Oklahoma, back in the 1960's. We used/sold thousands of the valves with ZERO issues. Parker Brothers ceased to make the valves (memory) sometime in the late 1990's. The Parker Brothers valve could be used in either methanol or ethanol for racing, and, in fact, Parker Brothers offered a valve with a huge orifice specifically for methanol use of the Stromberg type EE-1 Ford carb (a.k.a. Stromberg 97). The flat valve sat on an inverted flare in the seat. These valves had the advantage of a much more constant fuel level in the carburetor bowl. Plus the aluminum plunger could not become magnetized, which would allow rust particles to stick to the valve.
Daytona Carburetor is now advertising a valve that resembles this one. I have not personally inspected the Daytona valve, so will post no more about the Daytona valve, as I know no more about it.
This article I wrote explains more concerning the Parker, and other valves:
As far as the steel tip vs neopreme tip, there are proponents on both sides of the argument, and people on both sides whose opinion I respect.
Personally, I prefer those with the neopreme tip. Why? Check out this picture of a new old stock stainless steel valve, side by side with a used stainless steel valve that had been used with E-10: http://www.thecarburetorshop.com/Steel_needles.jpg
How well do you think the rusty valve on the right will seal?
The neopreme is not the issue, rather the lack of "staking" on new valves (covered in the aforementioned article).
And while this post is not an advertisement, I thought this information might be of interest.
Where possible, we furnish the neopreme-tipped valves in our rebuilding kit, as we feel they are superior. There are a few very early carburetors for which this is not possible, including most of the ones produced by Marvel in the 'teens and twenties. However, we can custom machine the stainless valves for the very few that want them for other kits. Less than 1/2 of 1 percent of our customers wish these stainless valves regardless of the vehicle, whether it be Chevrolet, Packard, Duesenberg, Bugatti, or Overland, thus there is no reason to mass-reproduce them. Each is custom machined, making for a significantly more expensive, and we feel, inferior, rebuilding kit.
