Carburetor Choke Disk Fits John Deere Late B TractorOne New Aftermarket Replacement Carburetor Choke Disk Fits John Deere B and 50 Tractors This brass carburetor choke disk (choke disc) is a direct replacement for the Marvel Schebler DLTX 67 and DLTX 73 single induction carburetors used on Fits John Deere (Fits JD) late model B and 50 tractors. The choke disk sits inside the carburetor's choke butterfly assembly, restricting airflow during cold starts to enrich the fuel mixture and allow the engine to