QuestionQUESTION: Purchased an MTD/Yardman snowblower with Tecumseh engine Snowking #LH318SA. About 6 to 8 hours on the machine. The engines\ always seems to run rough (from 0 time on) with occasional backfiring. Need partial choke for the smoothest running. In cold weather. The engine looses power when the choke is full "open". I owned a similar unit previously and alsways had the same problems with that smaller Tecumseh. Acts like it is running lean. Anything simple I can do?
Thanks
Jack
ANSWER: Hello Jack:
From your Description, it Sounds like the Carburetor is Out of Adjustment, there is Trash in the Carburetor Primary Jet or the Carburetor Anti-Diesel Solenoid is Not Opening Up Fully. The Numbers you Sent me are the Series Numbers. Send me the Model Numbers Off the Unit, Please. With these I can Locate the Proper Manual and Better Assist you. Thanks.
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. Thanks.
Respectfully
John
---------- FOLLOW-UP ----------
QUESTION: John
Thanks for the quick reply. TheTecumseh engine is 8.5 HP and model #LH318SA
Spec # is 156583H
Hope that helps!
Thanks again
Jack
AnswerHello Again Jack:
Thanks for the Model and Specification Numbers. This Does Not Appear to be an OHV Engine so the Valves are Not an Issue yet. When was the Carburetor Serviced Last? If it has been a Few Years, then Remove, Disassemble and Soak the Carburetor Overnight in Carburetor Cleaner (I Use Gunk). I have Found that Most People can Use a Breakdown/IPL and Disassemble the Carburetor Enough for Proper Cleaning. You Only have to Remove the Bowl, Float Pin, Float (if Applicable) and Needle Valve and Any Adjustment Screws that Go Into the Carburetor Body. The Welch Plugs Do Not have to be Removed. Then Soak the Carburetor Body and Parts in a 1 Gallon Can of Gunk Carburetor Cleaner Overnight. The Can has a Parts Tray Inside it for the Small Parts. Once the Carburetor and Parts are in the Cleaner, you can Replace the Lid for Safety and to Prevent Accidental Spillage. Then Blow Out the Passages with Compressed Air. Install New Parts if Required. Since this is a Tecumseh Engine, I have a PDF Site Addy that May Assist you Also. http://www.tecumsehpower.com/CustomerService/BSI.pdf. If this Carburetor has the Air Mixture Screws, then ****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 Farthest from 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. 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 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 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. Thanks.
Respectfully
John
