I am rebuilding my AFB (9000 series that transitioned to Edelbrock). In the rebuild kit the new float needles are solid, while the older ones had spring and rod to dampen the action I ***ume under the float. So should I just use the old ones or does it even matter?
Edelbrock makes a spring loaded needle set, not sure if they will work on this carb tho…? https://www.edelbrock.com/off-road-needles-and-seats-0935-qty-2-1465.html
Compare the weights of the needles. Something deep in the grey matter is telling me that the solid ones don't have springs but are closed by a higher power, gravity. Chris
Carter used solid needles in the 9000 series aftermarket carbs. The spring-loaded versions came in marine carbs. Could be more specific if the OP posted which 9000 series carb; there were lots of 9000 series O.E. carbs, and the marine versions (mostly) would utilize the spring-loaded valves. Jon
Thanks for your responses. This is a 9325, which has the Chevy throttle linkage, but works just fine on my Studebaker. I am sure it was not the marine version, as I bought it new. It has been running too rich and wanted to check the floats and clean out any garbage from the almost 30 years it has been on the car. I will just reuse the spring-loaded needles. Something seems to me they are there for a reason.
You might check the number, as 9325 is a thermoquad, not an AFB. And with apologies to Ryan, but there is a lot of activity here on the AFB carbs; a bit more information on the "9000 series": The original "9000 series" of high-performance CARTER aftermarket AFB carburetors (there were also some TQ's") consisted of: 9400, 9500, 9625 with GM linkage (400, 500, and 625 CFM) 9501, and 9626 with Chrysler linkage (500 and 625 CFM) 9627 with Ford linkage (625 CFM) These were superseded by adding an EGR port (with a plug) as follows: 9410, 9510, 9635 GM linkage 9511, 9636 Chrysler linkage 9637 Ford linkage Note there were no 750 CFM aftermarket carbs originally. Later, a 9755 (750 CFM GM linkage) was added after a conversation I had with a couple of the engineers about a 750 CFM I made for a motorhome from a Comp Series 4760 with choke and fast idle parts from a donor 9625. It solved Dad's motorhome problem, and it also solved the same problem on the motorhome belonging to one of the engineers. After the Federal Mogul redesign, there have been other versions of which I have no knowledge. The Carters can be distinguished from the redesign, as the numbers of the Carters mentioned above are suffixed by the letter S, the redesigns, by the letters SA. I don't know what the suffix is on the other FM's. Jon
I have personally swapped back and forth between the spring loaded and the solids. I could not tell any difference. I’m not sure what the purpose of the spring is. I personally would not want to reuse the old ones when rebuilding a carburetor.
The spring-loaded fuel valves were developed for off-road and marine use. Boats have the bouncing bow, off-road have rocks and holes (so do Missouri roads! ) The spring-loaded valves are designed to reduce the bounce to get to the float, and also to maintain a more uniform fuel level in the bowl. It doesn't matter which is used in highway driven vehicles; although the spring-loaded ones might be useful for the Missouri pot-holes. After the last big rain, I saw a tourist sitting in a lawn-chair fishing in one of the larger local pot-holes! Jon