Lawnmower sputtering

I have a Yardman with a Honda engine. It starts fine but when the little choke level finishes and closes it begins to sputter badly. So then I pull the choke lever back and it runs for 20 seconds fine, only to begin choking again.

I'm a novice but spent alot of time figuring out how to remove the carb and clean it. twice. Doesnt seem to help. Checked the air filter.

What else could it be? gasline maybe?

 

The choke should be opened when the engine is hot. I wouldn't take anything apart. Open the choke with a screwdriver while it's running. The engine should run smoothly.

 

I think your terminology might be backwards... the choke closes by hand and returns on it's own to the open position. If it runs better with the choke closed, then there is a restriction in the carburetor.

 

yea :-) i'm sure I'm blundering the terminology here. TO start the mower I "pull" back a lever which I assumed was the choke. Then I pull the start cord. Mower starts immediately and the lever slowly closes after about 10 seconds. As soon as this lever closes the engine sputters, revving up and down. Usually I have to restart it once or twice. Eventually it runs fine after about 10 minutes of running.

So cheese, to your point, I'm actually "closing' the choke when I'm pulling it? and its slowly moving to the "open" position?

If so, you say this is a restriction in the carb? Wow I cleaned this out - again a total novice here. But flushed it with cleaner and some thin wire in the holes. really didnt find anything either. when I sprayed the cleaner through it shot out of all the holes, making me think all was clear.

 

That's correct. You are actually closing the choke when you pull it. Remove the air cleaner & watch the choke while it operates. If it opens & the engine sputters, tighten all the screws & hold down nuts or bolts on the carb. It sounds like there is a vacuum leak.

 

Pulpo's explanation of the choke operation is accurate, and there could possibly be a vacuum leak.
I would confer with cheese however and this might be as simple as some sediment or old/bad fuel residue in the bottom of the bowl.
Might be worthwhile to simply remove the bowl and have a look and spray some cleaner up the carb.

I might also be inclined to attempt to keep it running long enough for it to warm up good (2-3 mins) and proper and see if it does any better.

If none of that has any success removing and cleaning the carb would be next.
You did however mention it is a Honda engine on a yardman? (Wow never seen that, maybe I have been out of the game a while, but geez) My last experience with a Honda carb was needle and seat issue, I ordered a needle (24 USD) which remained on back order for over 6 weeks. Found out they had a replacement carb in stock for 17USD all the while.