I was on the old forum a while back. I had to re-register.
Usually I can fix these small engines myself as I have been doing it for many, many years, BUT this one is being a pain in the A$$.
Coleman Powermate Generator circa 1997, I purchased brand new.
Briggs 10HP model 19E412
Walbro LMT 172 Carb (19E400 carb I believe)
Coleman Generator always ran fine, have owned it since April 1997, only used it maybe twice a year since then, but always maintained oil in like new condition, and kept gas fresh.
Well, it's running lean, and I have taken the carb apart and inspected it, it was clean, but I disassembled it all and cleaned it with carb clean and compressed air.
Put all back together, same thing, will surge unless you run it at 1/2 choke or better. So, I figured, I'd get an over haul kit (497849) for the Walbro LMT 172.
So, I completely disassembled it again, this time taking the throttle shaft out, bushing, choke and shaft, idle mixing circuit welch plug I guess they call it.
Pulled out the old fuel inlet seat and pressed in a new one, changed the main nozzle, float is good, new needle etc...
I dunked it in the new carb acid for 45 minutes, cleaned it real good, completely blew through every port and orfrice etc with a needle blow gun. Keep in mind this thing was clean to begin with, at least I couldn't see any dirt or carbon build-up, varnish, nothing.
So after reassembly, I get the same exact damn problem. I am very fed up with this non adjustable piece of crap....only idle mixture can be adjusted, no other adjustments can be made.
Does anyone know any tricks how I can richen this thing up a little without running on half choke....?
Is the a different main nozzle I can try, I'm not sure what to do. The generator runs well under electric load at 1/3 choke. With no load, you have to run it at 1/2 choke to be smooth, if you take it off choke completely, it just surges like crazy, LEAN........Thank you all for any help or advice you can give me....Rich