The Marvel-Schebler Model DLTX Carburetor is a horizontal type carburetor used on John Deere tractors. To meet the specific engine requirements of the individual tractor on which the carburetor is installed requires a different size jet, nozzles, venturi, throttle: and choke operating levers, etc. For this reason, when ordering parts, always refer to the individual carburetor service parts list for the engine on which the carburetor is installed.
The Model DLTX Carburetor consists of two castings:
1. The throttle body casting which contains the air inlet.
2. The fuel bowl casting.
The throttle body casting contains, in addition to the throttle assembly, a venturi machined in the casting and the choke assembly. Cast iron material is used for ruggedness, all passages, whenever possible, are drilled within the casting to prevent any fuel leaks to the outside of the carburetor because of shrunken gaskets or defective hole plugs.
The Model DLTX Carburetor is completely sealed against dust or dirt. All air entering the fuel bowl of the carburetor must first pass through the air cleaner. The throttle shaft bearings and the choke shaft bearings are sealed to eliminate dust and dirt entering at these points. New throttle shaft bushings can be installed when the bearings have become worn.
The float mechanism is contained in a cast iron fuel bowl (Figure 1) on all DLTX models with the exception of Model DLTX-26 and Model DLTX-46. In these two carburetors, the float assembly is retained by the throttle body casting surrounded by a stamped metal fuel bowl.
All models have a fuel strainer to prevent dirt and foreign substances from entering the fuel bowl.
A throttle lever stop spring is provided to prevent uneven running or “hunting”(governor opening and closing) when the load is released and the governor closes shut, turn the throttle stop screw against the throttle lever stop spring until the “hunting” is corrected and idling is satisfactory, normally there is 1/12" clearance between the throttle stop screw and the throttle lever stops spring at fast idle.
While there are many variations produced by combining the types and sizes into a specific application, all Model DLTX carburetors incorporate the same engineering principles and are alike from a functional standpoint.
