Briggs and Stratton 20Hp runs great without the air filters in place - not dirty

Briggs and Stratton 20Hp on craftsman lawn tractor runs great without the air filters in place and they don't seem to be dirty. It dies when the filters are in place and at high rpm's. Cleaned carb, changed oil, filter and plug.

Also, choke not opening when lever is released! New to all of this and wanting to learn. Thanks in advance to any good ideas.

 

Have you purchased new filters and tried them? Even if a filter looks clean it may not be allowing enough air through for the engine.

 

That was (one of) my plan(s), thanks. Other issue: what is supposed to allow the choke to reopen? I lower the lever from out of the choke position and it stays choked.

 

What engine?

if it's a single cylinder engine, change the choke shaft.

 

Please add Model # and type # of Briggs engine.

 

Sorry so long in replying - been away. The tractor is a Craftsman 20Hp 42" mower (#917.276813). The engine is a Briggs (#31P977-0635-E1).

 

Fix the choke issue first,,,you may have dirt in the carburetor where the choke shaft rides, some times dirt build up in the hole where choke shaft mounts in carburetor. Make sure also you change out the Pra filter or clean it really good, also if you cleaned the air filter I have found sometimes all the soap used to clean it doesn't get all washed out and it will cause the carb to choke down, also make sure it is good and dry, but with that choke sticking it will continue to run sick untill it is fixed first. If choke is off have you tried a NEW air filter. Anyway that's my two cents worth,,good luck.