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The machine began to hunt and run rough (popping) at the beginning of the season and would run well with partial choke. I thought I would take down the carb to clean it and clear this hunting issue. Machine continues to hunt with the following actions taken:
[*]clean carb, [*]clean full tank, [*]clean fuel line[*]new spark plug[*]replacing the carb (twice) with ebay purchases[*]Opening the low idle jet[*]Opening the main jet

I am at my wits end and was going to look at the governor as a possible cause of the surging. Any help or suggestions would be greatly appreciated.
 

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Welcome to the SBF from Central Penna.
 

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Check/change air cleaner
Check gas cap vent
Check to see if water in fuel
Check gaskets mounting carburetor
Check tightness of bolts securing carburetor
 

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I've had the black plastic spacer behind the carb warp and cause a vacuum leak, which will cause it to hunt. Did you get new carb gaskets with the carbs you bought? One other thing to check is the valve lash.
 

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Hunting usually means you are running lean. If you have an idle mixture screw, you can richen it with that, if not, you will have to clean the carb again, or maybe the fuel filter needs to be replaced or cleaned.
 

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The machine began to hunt and run rough (popping) at the beginning of the season and would run well with partial choke. I thought I would take down the carb to clean it and clear this hunting issue. Machine continues to hunt with the following actions taken:
[*]clean carb,
[*]clean full tank,
[*]clean fuel line
[*]new spark plug
[*]replacing the carb (twice) with ebay purchases
[*]Opening the low idle jet
[*]Opening the main jet

I am at my wits end and was going to look at the governor as a possible cause of the surging. Any help or suggestions would be greatly appreciated.
If you can get the machine to run steady with the choke..the governor is not at fault.
It is almost always the low speed circuit running lean on these small engines.
Your replacement carbs may even be lean.

In general the only governors that need tuned are generator governors as they have to live on the verge of hunting to keep the droop low/ as the frequency goes down when engine speed goes down.
A properly tuned carb can get you in the five percent droop range... The governor droop is usually over 10 percent on non generator equipment...So the hunting almost always goes back to the low speed circuit being lean causing high speed no load hunting.
You can try raising your idle speed to about 2200 or so.. that way while it's hunting if it's actually bumping the idle speed screw it will have less of a recovery to make after overshoot as you are restricting overshoot ...that will sometimes help with a low speed circuit problem causing hunting ..without a load the throttle is just barely cracked open..so the range is very narrow between proper speed and idle.
A governor overshoots during it's action..so when the RPM drops..the throttle opens up ..the engine speeds up..closes the throttle and overshoots as well...if the the low speed circuit is crippled ...the governor will react faster than the governor drifting to correct itself from the inertia which causes the overshooting..it is the stuck in then endless cycle







Sent from my LM-Q710.FG using Tapatalk
 

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If you have pulled the pilot jet and opened it a bit as you say I'd also look for a short as mentioned above. It could just be a coil winding going bad, cracked boot/cap on spark plug lead, or kill wire chewed/chaffed also mentioned above. Plug in your ODBII and see if you're getting code P0300:devil: Try old school trick of letting it run in semi dark area and spraying water mist around spark plug area, recoil shroud and dash key switch if you have it. Look for arcing. It was fairly common for the early Powermores to have failed coils and even NIB replacements.
 

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There is a gap next to the dip stick tube right under the tank.. you can see the governor bracket where it is on the shaft... You will see a little clip... You can spray that shaft and clip if you think the governor may be dragging a little.. it's rare but you could have corrosion there
Edit:Add
You can also see it on the side as well looking at the gap at the end of the starter.

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