Small Engines (Lawn Mowers, etc.): carburetor adjustment, briggs and stratton, air mixture

Question
QUESTION: I just cleaned carb on Briggs and stratton 8 hp(snow blower). Carb has 3 adj screws..2 on carb body and 1 on bottom of float bowl.  Adjusting main jet mix (bot of bowl) for high rpm renders throttle control ineffective!  Same with hi speed ? adjustment! help!

ANSWER: Hello Rich:

>>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.****
>>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. Be Safe and Happy. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 5 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

---------- FOLLOW-UP ----------

QUESTION: Sorry, my engine is 8 hp tecumseh (ariens sno blow)...4 cycle.  Mix screw at bowl bottom is out 2 1/2 turns and if I adjust in even 1/2 turn, engine is revving high rpm and throttle will not change it regardless of position (no affect at all).  Same with other mixture screw!

Answer
Hello Again Rich:

>>If you Move the Governor Arm, does the Engine Speed Change?
>>Did you Put the Governor Linkage in the Correct Hole when you Attached the Carburetor to the Engine?
**The Throttle Cable Attaches to the Throttle Control Bracket. The Cable Moves a Slide that Moves a Pivot. The Pivot has the Spring  Attached to it and the Other End of this Spring Attaches to the Governor Arm. The Solid Link Connects to the Governor Arm and goes to the Throttle Shaft on the Carburetor.  When the Throttle Cable is Moved it Moves the Pivot and the Pivot Pulls the Spring. The Spring Pulls the Governor Arm and the Governor Arm Moves the Throttle Shaft. Usually the Spring is in the Lower Hole in the Governor Arm and the Solid Link is in the Top Hole of the Governor Arm.**
>>Did you Loosen or Remove the Governor Arm from the Governor Shaft when you Removed the Carburetor from the Engine?
>>The Following is an Instruction File I Made for Setting the Governor Arm Correctly. Any Input is Appreciated.  
>>If you Removed/Loosened the Governor Arm from the Governor Shaft or Put the Linkage in  a Bind when the Carburetor was Removed, 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.**
>>As Always, 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. Be Safe and Happy. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 5 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

**Note: If the System does not Allow for more Follow-ups, then Please Start a New Question Line Starting from where we Leave Off in this Question Line. Simply Remind me that we are Already Working on this Unit.
>>Thanks Again.

>>Respectfully

>>John