Phantom Idle Jet

[Roger440IC]

I have a question regarding the idle jet on a TSX-756 carburetor. I'm in the process of rebuilding the carburetor on my early 440IC and have had to pick up a second TSX-756 in order to get enough good parts to build one good one. When I took them both apart I found that neither of them have an idle jet screwed into the body. Figure 60-5-6 on page 60-5-3 of SM2024 clearly shows the idle jet screwed into the body and I've been able to get the jet, part # 49-101-L, from JD. Should I put this in or not? It seems strange that two carburetors, taken off two different machines would have this missing. Is it known that the 440 runs better without the jet? Thanks for your help, Roger.

[CELSESSER]

Roger,
The idle jet controls air flow into that carb . With wear on the throttle plate shaft bushing and felt there is usually too much air getting in and the idle jet needs to be turned in all the way to make them idle better. After I rebuilt mine the idle needle kept backing out due to vibration. Either they have vibrated out or the passages were plugged and therefore they didn't make any difference in adjustment and were left out.
Just my .02

Chuck

[Roger440IC]

Chuck, thanks for the input. I'll put it in and give it a try. Roger