Small Engines (Lawn Mowers, etc.): Engine Governor setting, mixture adjustments, air mixture


Question
Hello.  I have a 26hp Briggs ELS engine.  I had to split the case and remove a rod that bent and went into the engine.  There was no damage inside of the engine (Checked).  When I put it all together on the mower, I set the governor by the static method in the manual.  It still would not idle correctly.  What is the correct method to set the governor lever and throttle link?

Answer
Hello Tony:

>>A Quick Question First, Please.
>>Did you Hone the Cylinder that you Pulled the Piston from when you Replaced the Bent Rod?
>>If No, then
>>The Compression on that Cylinder Usually will be Lower than Specifications and with the Lower Compression, the Engine will Usually Surge at Idle due to a Compression Imbalance between the 2 Cylinders.
>>Anytime a Piston is Removed from a Cylinder the Rings become Unseated and have Trouble Reseating due to a Slick Cylinder Wall.
>>The Honing with Fine Stones Roughens up the Cylinder for the Rings to Reseat.
>>If Setting the Governor and Checking the Carburetor Mixture Adjustments Do Not Correct the Idle Problem, then
>>Remove the Piston Again and Hone the Cylinder.
>>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 ( Usually the H 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. **Carefully Use your Finger and Move the Governor Arm to Rev the Engine (on Chainsaws and Trimmers Use the Trigger to Rev the Engine) Until you Reach Max RPMs (on Chainsaws and Trimmers, the RPMs are Not Set to MAX. Set to Max and then Reverse the Setting Screw 1/4 or 1/2 Turn. If the H Mixture Screw is Set too High; the Engine will be Starved for the Oil in the Gas and Damage the Piston and Jug/Cylinder) and the Engine is Running Proper at Full Throttle Up a Grade and for Chainsaws and Trimmers they Do Not Bog Down Under a Load. 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 Rapidly Throttling from Idle to Full Throttle. Reset the Engine Idle if Required.****
>>Send me the Model and Type or Spec Numbers Off the Engine, Please. With these I can Locate the Proper Manual and Better Assist you. The Model Numbers May be Stamped Into the Blower Housing (metal engine cover) Above the Spark Plug or the Muffler. Many horizontal shaft, overhead valve engines have these numbers stamped into the OHV rocker cover. However, on certain overhead valve powered generators, the equipment manufacturer installs a decorative chrome rocker cover OVER the Briggs cover. If your engine has a decorative cover, it may be necessary to remove it in order to locate the Model, Type, and Code. If this is a Briggs and Stratton  Engine, then you can Also Use this Site Addy; http://www.briggsandstratton.com/maint_repair/BS_modeltypecode.pdf for Assistance in Locating the Model, Type and Code Numbers of a Briggs and Stratton Engine.  
>>If you Hit a Snag or this Does Not Correct the Problem,  I Hope to be Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Be Safe and Happy. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 3 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. All Follow up Questions are Accepted at Any Time. Comments and Ratings are Greatly Appreciated. Thanks.

Respectfully

John