Small Engines (Lawn Mowers, etc.): MTD Snowblower, blown head gasket, crankcase oil

Question
I have a MTD Snowflite snowblower. It has a 5 HP Tecumseh engine.  I am having a lot of gas in the oil and it will not start.  Any idea of what the problem may be.

Answer
Hello Rob:

This Problem is Usually Caused by the Carburetor Needle Valve Not Seating Properly and Flooding the Engine when the Engine is Not in Use. Usually it will Cause White Smoke if the Engine Starts and Runs. However Depending on the Model, there are Several Other Possible Causes Also. Use the Sections of the Following Instructions that Apply to your Unit to Locate the Cause of the Crankcase Contamination. Usually the Gas in the Crankcase Oil or White Smoke is Caused by a Bad Diapgragm in the Fuel Pump, a Blown Head Gasket between the Cylinder and Push Tube Galley (OHV Engines Only), the Crankcase Vent Stuck/Frozen/Broken or the Carburetor Flooding the Engine. 1- Block the Outlet Port and Pull a Vaccum on the Fuel Pump (if you Unit has one). If it Holds Vaccum, then it is Good. If Not, then the Diaphragm is Busted and the Pump Requires Replacing.  If the Fuel Pump is Good, then Check the Crankcase Oil for Gas Contamination. If the Crankcase Oil is Contaminated, then Drain and Refill the Crankcase Oil with Fresh Oil. 2- **If the Mower has a Manual Gas Shut Off Valve:  Check the Manual Cut Off Valve and Make Sure it is Cutting Off the Gas Flow to the Carburetor. If Not Dtopping the Gas Flow, then Replace the Valve. If the Mower Does Not have a Manual Cut Off Valve: Install a Manual Cut Off Valve and Turn Off the Gas Flow when the Engine is Not in Use.** 3- If the Valve is Good or has Been Installed, then Remove the Cylinder Head. On the OHV Engines the Head gasket will Blow Between the Cylinder and the Push Tube Galley. This Allow Oil to be Sucked Into the Cylinder from the Crankcase and the Extra Oil is Just Enough to Cause the White Smoke. 4- Check the Crankcase Breather and Make Sure it is Clean and Operating Properly. If the Crankcase Breather Sticks, then Oil is Pulled from the Crankcase into the Carburetor Throat and this Causes the White Smoke. 4- I Listed the Possible Causes in the Order they Usually Occur. I have had Some People Ask me Why I do the Diagonstics in the Order I Use and it is Simply that Over the Years I have Made a List of the Equipment, the Models and the Problems they have When I Receive them for Repair. Then I Listed the Cause and Repairs Made. Thanks for Using All Experts. 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