Marvel Carb, choke relief spring?

My choke plate has a semicircle cut into it, and flapper behind it that can plug the hole. I was looking over a VAC marvel guide online, see pic, and it shows a spring that attaches to this choke flapper. Should my 310B have a sping, there isn't one right now, not sure how it would attach.

Also, anyone have a rough idea how many turns to back out the throttle and main jet needles for a 'factory spec'?

Ed

• Manual

Do you recall if there is a "return assist" spring on the throttle lever of the carb, similar to the choke lever? i.e. should the throttle lever be spring loaded such that it wants to resort to closed if nothing else is pulling on it? My choke lever has this but throttle does not.

Thanks,
Ed

When the engine is running the centrifugal force on the governor tries to force the throttle closed and is opposed by the spring (governor spring) that connects the right side governor arm to the throttle linkage from your hand/foot throttle. You set the engine rpm by manually tensioning that spring with the hand/foot throttle and the governor maintains the set rpm by pivoting in response to the centrifugal force germane to the rpm departure of a load change. The carb throttle fly is directly connected to the governor left arm by linkage.

If you add a return spring you will just be changing the point of equilibrium between the throttle linkage governor spring and the centrifugal force of the governor. To get back to square one you would have to increase the open position of your hand/foot throttle to cancel out the tension of the return spring, so it would not have any operational function anyway. I can scan & e:mail governor & linkage adjustment info in the 300B manual if you want it. It should be the same as your 310B. I would be leery of a light pen spring on that choke flapper. These springs can break or come adrift (backfire episode?) and will end up swallowed. It may also hang up on an intake valve and live long enough to damage the valve and/or seat. I have a junk TSX 114 carb that has the same p/n spring as the TSX 635 carb. The fly & baffle are probably the same also. The fly is stamped for 10� bevel and should fit most 1-�� (nominal) throat carbs. If your carb is a TSX 635 or similar you are welcome to it. Joe

Also need an exhaust elbow (that connects the muff and manifold), found a new one online for $49. Have you seen them cheaper anywhere?

Ed

First time I have used the new contact form, if it doesn't get through my email address is [email protected]

ID tags can be near invisible on these carbs. May be located as in the pic or on the round part opposite side of the fuel inlet fitting.

I think that is an ok price for the elbow, I paid $80 to have mine welded several years ago.

Joe

Joe

Just found the prelim settings for the screws, see image.