Arm loose, worn out or damaged? The straight up arm on this particular linkage is usually used on the B, IB, C, and CA model Tractors. Used on the TSX series Marvel Schebler Carburetors.  This is a brand new piece. 
 
B&B TECH TIP:   If your Carburetor's throttle shaft is loose in the throttle bore, this will usually NOT take the looseness out of the throttle shaft. In most cases, the throttle bore wears out before the throttle shaft. The throttle bore will need to be bushed, or sleeved depending on how loose the throttle shaft moves in the bore. Take it from someone that rebuilds a lot of customer's Carburetors for their AC Tractors!