Hello, I'm Mike.
I'm happy to help you today. Please post back to this thread for any questions or concerns, either before or after payment.
A test to try would be.to have someone squeezing primer bulb to see if it helps keep engine running. If it does I would service fuel pump. Of course you have a CTO pump which is a 500.00+
Item to replace.
Another thing that we see with those Johnson motors that do not have idle air mixture screws.in the carb that can be richen up as the engine starts wearing internally is this type of.compliant. A good competent dealer can successfully tenet the carbs.for.this type of.problem. a test to see if the fuel mix is leaning out would be a quick tap on the choke to see if the engine pick back up in rpm for a second.
Hope this is help you can use.
Best of luck,
Mike