Small Engines (Lawn Mowers, etc.): Honda GCV160 Surging, air filter assembly, honda gcv160

Question
I have a Craftsman mower with a Honda GCV160 5.5hp engine with serial # GJAEA-3654910.  This mower ran great until during a garage cleaning a shelf fell on the carburetor/ air filter assembly and then it started surging.  I have replaced all of the gaskets, bolts, air filter housing, air filter, spark plug and cleaned the carburetor.  It still is surging.  The automatic choke seems to return to starting position slower than it used to, but appears to be operating.  I took my mower to a local small engine repair shop that told me that this is normal for a Craftsman Honda engine and that I should live with it.  What a bunch of crap.  Is it possible that I need to readjust the carburetor and how would I go about that?

Any further help would be appreciated.

Answer
Hello Shane:

I Agree; that Does Sound like a Bunch of Crap. Honda and Other Small Engines are Not Designed to Surge or Hunt at Any Speed or Condition. This will Not Happen Unless there is a Restriction in the Carburetor Passages, the Air Mixture is Not Set Correctly or the Governor is Not Set Correctly. There are a Few Other Possible Causes, but these are the Most Common. 1- Try Setting the Air Mixture. The Following is the Instruction File for Setting the Air Mixture Screws. Any Input is Appreciated. The Procedure is the Same for 1 or 2 Mixture Screws, Just Use the Instruction File and Skip Over the Section with the Missing Mixture Screw. Now Setting the Air Mixture Screws:  ****Turn the Idle Air (L) and Main Air (H) Mixture Screws In Until SNUG **Do Not Jam** Then Reverse Both Screws 1 1/2 Turns. Set the Throttle Full Open, Start the Engine. Turn the Main Air (H) Mixture Screw Clockwise Until Proper Revs are Obtained. Occasionally you May have to Turn this Counter Clockwise to Achieve the Proper Revs. Now Allow the Engine to Idle. Set the Engine Idle Screw (Not Idle Air) so the Engine will Stay Running if Required. Now Set the Idle Air (L) Mixture Screw so there is No Hesitation when Throttling from Idle to Full Throttle. Reset the Engine Idle if Required.**** 2- If this Did Not Correct the Problem, then Set the Governor. It May have been Moved Slightly when the Shelf Fell on the Carburetor. The Following is an Instruction File I Made for Making this Adjustment. Any Input is Appreciated.  If you Removed/Loosened the Governor Arm to Remove the Carburetor, then Reset the Governor. **To Reset the Governor; Loosen the Governor Arm Bolt and Turn the Governor Shaft Clockwise Until it Stops. Using the Governor Arm Hold the Carburetor to Full Throttle. Now with the Shaft Full Clockwise and the Governor Arm and Carburetor Held at Full Throttle, Tighten the Governor Arm Bolt. If the Engine Still Runs Full Throttle, then Reverse the Rotation of the Governor Shaft, but Still Hold the Carburetor at Full Throttle with the Governor Arm. If it Still Runs at Full Throttle, then Check the Internal Governor.** Please, Do Not Hesitate, If you Hit a Snag or this Does Not Correct the Problem, I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Comments and Ratings are Greatly Appreciated. Thanks.

Respectfully

John