Carb information for 1948 with J motor


New Member
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6:48 PM
Apr 12, 2018
I am just finishing up this 2 year restoration and need information on carburetors. I have the Tillotson ML15B which came with the unit. I got it running pretty good initially but then quit. With starting fluid it would fire but not keep running. Cleaned the tank, fuel lines, etc. with air hose but no change. Decided to take the carb apart and clean with carb cleaning solution. Unfortunately while taking it apart I managed to destroy what is listed in the manual as the "main jet (nozzle). Finally got it out but is not reuseable. Does anyone know where I can get parts for this carb. The illustration in the manual lists the proper carb as an ML-5B. The ML-15B looks identical to th ML-5B. I don't know what the difference would be but I think the ML-15B would work O.K. since I had it running before I destroyed the jet. Been checking everywhere I can think of but can't seem to find the part I need. Anyone have any ideas????

I have been thinking of replacing the carb with a Mikuni but don't know which model, if any, would work. I previously had good luck with tuning a Mikuni on a Cushman I rebuilt a few years ago but haven't been able to find any cross reference information. Anyone have any suggestions???? Hate to give up now!!

Update 4/20 I think the only difference on the carbs is that the ML5B takes fuel from the top and the ML15B takes the fuel from the side. Not a big difference but that side entry can be painful on the ankle if your not careful when starting the motor. I am posting a couple of more pictures from the ML15B that I have. The pics are from the part I have partially destroyed. I think it is the "main jet" attached to the emulsion tube. It doesn't appear that the two can be separated. The pictures in my carburetor diagram describes it as the "main jet (nozzzle)". I found a carb refurb kit for the ML15B with pictures of what is included in the kit and none of the parts are like the one I need. It looks like the jet (or top part) is there but no emulsion tube. In doing further reading on carburetors it seems like the part I have is called the "emulsion" tube, however none of the pictures I have seen shows the top part that has the threads on it. Looking at my part very closely it looks like it is made all as one part. I think the threaded part on top is the main jet and is attached to the emulsion tube. Unless I'm totally wrong the parts cannot be separated. Surely others have had similar issues. ANY information would be appreciated.

One final note when I was reading through the FAQ's someone mentioned having success by putting a 22mm Mikuni on their Whizzer. I believe it was on a newer Whizzer and not a vintage one. Has anyone done this on a Whizzer with J motor?????

Thanks for any response.


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