does this appear to be the one Ty?Its a very early 3F series brass nut version.This came in some parts I was given with a model 1 Rotomo,so it wasnt actually on a mower.I think you can get how it all goes from the Images.
Let me know if it is accurate from the parts manual.The first Image shows the only difference I can see between this and a std 3F.Jet and block are unmarked,Im under the assumption the jet and block sizes may be greater,especially if its a marine or high load industrial application.small bowl nut and large slide screws you would normaly associate with a 3L are the only other differences I can see.

Regards Mal.[Linked Image]
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