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wrote:

BIG SNIP

Put some gas directly into the cylinders and it fired, then died out.

I pulled the carb. Figuring the gas tank change/refill must have sent
some debris/crud/whatever into the carb.
Opened up the bowl and observed float valve not coming out of
its hole by gravity. Gently unstuck it. took it out and wiped it
clean. Internals of the carb were spotless BTW. Rubber tip on
float valve is clean and un-damaged.
Examined High-Speed (rich/lean) screw.(The one on the bottom
that feeds the bowl) Real clean , undamaged.
Pulled Low-Speed (rich/lean) screw.(Long brass needle valve
on top) Tip of valve has an offcenter crease on it but looks
sound. (The crease didnt just appear so it isnt the cause of my
immediate problem). Reassembled carb. Blew air thru the fuel inlet
pipe of carb. Heard airflow that I didnt before.
Reinstalled Carb. Fired it up. It ran VERY rough but ran. Turned the
low speed screw to all the way rich and it chugged out. Back to
lean and it ran rough again.

Clearly I didnt put the upper screw in at the exact depth it came out
at. Close , but no cigar.

Q: Anyone know what the initial settings for this carb should be?

Upper - low speed needle - idle initial setting is 1.25 turns open.
Lower - high speed needle- initial setting is 3/4 turns open.
I
know them for my tractor carb (all the way closed then 1.5 turns
out) but not this one. My fault for careless disassembly.
Q: Engine has J6C plugs in it. Previous post calls for J4C and engine
spec calls for J4N. What SHOULD be in there?

J4C is the new designation for the J4J/J4N. It has a copper core.

Rob