Small Engines (Lawn Mowers, etc.): Tecumseh 3.5 HP Snowblower Carb Setting, ariens snow blower, air screw


Question
Hello John,
  I have a Ariens Snow blower with a 3.5hp Tecumseh engine (H35-45515k Ser: 8191B) that I believe I need a carb setting for.  On the bottom of the assembly (under the carb) there is one screw with a spring wrapped around it.  My son messed with the screw (this is the only thing he adjusted) and I do not know the original position (how many turns out the screw was).  The snow blower was running great, it just needed gas.  I was able to adjust the screw in order to get the snow blower running again however I am getting some backfiring and the muffler seems as though it's getting hotter than normal.
  Do you know the number of turns to set this screw out at?  Or can you offer advice to set it myself?

Thank you so much for your response in advance,
Kevin

Answer
Hello Kevin:

>>The Following is an Instruction File I made for Correcting this Problem. Any Input is Appreciated.
>>****All the Carburetor Adjustments are the Same for Lawn Mower and Trimmers.
>>There are Several Location for the Air Mixture Screws.
>>The Idle Air Mixture Screws are Usually Located at the Top of the Carburetor Bowl and the Top of the Carburetor Body.
>>If the Main Air and Idle Air Mixture Screws are Side by Side on the Side of the Carburetor, then the Idle Air is the Nearest to the Engine.
>>The Main Jet Air Mixture Screw is Located in the Bottom of the Carburetor Bowl or Beside the Idle Air Screw on the Side of the Carburetor Body.
>>The Engine Idle Screw is Usually Easy to Identify because you can See where it Makes Contact with the Carburetor Throttle Shaft Plate Stop Ear. The H and L Air Mixture Screws Go Into the Body of the Carburetor and the Tips Cannot be Seen.
>>Some of the Older Model Carburetors have the Main Jet Mixture Screw Straight in from the Top of the Carburetor Body (this is Rare anymore).
>>If you have Cleaned the Carburetor (Disassembled and Soaked Overnight in Carburetor Cleaner (I Use Gunk). Then Blow Out the Passages with Compressed Air and Install a New Kit if Required.
>>Now Setting the Air Mixture Screws:  
>>****Turn the Idle Air and Main Air Mixture Screws In Until SNUG **Do Not Jam** Then Reverse Both Screws 1 1/2 Turns.****
>>Holding the Throttle Full Open, Start the Engine.
>>Turn the Main Air 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 Mixture Screw so there is No Hesitation when Throttling from Idle to Full Throttle.
>>Reset the Engine Idle if Required. If This Carburetor has a Single Air Adjustment.
>>Use the Section Above that Pertains to Full Throttle RPM Air Mixture Screw and then Adjust the Screw if Required to Eliminate Any Hesitation when Rapidly Throttling from Idle to Full Throttle.**
>>1- http://www.repairfaq.org/samnew/lmfaq/lmclctc.htm   
>>2- http://www.cpdonline.com/692509.pdf   .
>>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. Have a Happy Holiday Season and 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. Follow Up Questions are Received Anytime. Comments and Ratings are Greatly Appreciated. Thanks.

Respectfully

John