QuestionI have a 18hp Vanguard V-Twin (model#3504477) that is blowing white smoke, lost power, and is soaking the air filter with oil. I think the head gasket is blown and also wonder about the cylinders and/or rings. Do you think it is the head gasket?..if so can a "do it your-selfer" handle the job?. I already replaced the fuel pump (which is actuated by pulsating crankcase vacuum from the engine), this was the problem a year ago when the engine was acting the same way. Replacing the fuel pump didn't fix it this time, I still see oil squirting out into the air cleaner base. Thanks for your help.
AnswerHello Joe:
>>Changing the Head Gasket is Not a Hard Repair.
>>Have you Checked the Crankcase of Contamination by Gasoline?
>>Usually the White Smoke is Due to the Following;
>>The Following is an Instruction File I Made for the Gas Smell in the Crankcase Oil. Any Input Concerning the File is Appreciated. >>Depending on the Engine Model, Usually the Gas in the Crankcase Oil or White/Blue Smoke is Caused by the Carburetor Float Needle Valve Not Seating Properly and Allowing the Gas to Flood the Carburetor and Engine. Then the Gas Seeps by the Rings and Enters the Crankcase and Contaminates the Crankcase Oil.
>>The Smoking is Caused Not Only by the Flooded Crankcase but can be Caused by 1 of the Following; a Bad Diaphragm in the Fuel Pump, a Blown Head Gasket between the Cylinder and Push Tube Galley, the Crankcase Vent Stuck/Frozen/Broken or the Carburetor Flooding the Engine.
>>1- Clean the Carburetor and Replace the Float Needle Valve (and Seat if this Model has One). A- **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 (if Applicable), Float Pin (if Applicable), 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.**
>>If the Carburetor Float Needle is Good, then;
>>2- Block the Outlet Port and Pull a Vacuum on the Fuel Pump. If it Holds Vacuum, 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.
>>3- **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. A- If Not Stopping the Gas Flow, then Replace the Valve. B- 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.**
>>4- 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.
>>5- Check the Crankcase Breather and Make Sure it is Clean and Operating Properly.
>>6- If the Crankcase Breather Sticks, then Oil is Pulled from the Crankcase into the Carburetor Throat and this Causes the White Smoke.
>>7- If the Crankcase Oil is Good, then Check the Gas Tank Cap and Ensure it is Venting the Tank. If the Gas Cap is Not Venting the Tank, then Pressure Builds in the Tank and the Pressure Pushes Gas by the Carburetor Float Needle Valve and Floods the Engine and Crankcase Oil.
>>The Following is a Basic File I made for Setting the Valve Clearances. Any Input is Appreciated.
>>**I Do Not Use the Setting Called for by the OEMs. I have Found that the Following Works Best.
>>Remove the Valve Cover (on the Dead Cylinder for Twin Cylinder Engines).
>>Check the Push Tubes and make Sure they are Not Bent.
>>Set the Cylinder you are Setting the Valves on to Top Dead Center on the Compression Stroke When Setting the Valve Clearance. Now Loosen the Valve Adjuster Lock and Using a Blade Style Feeler Gauge, Set the Intake Valve Clearance to .004in -.006in and the Exhaust to .006in - .008in. Loosen and Tighten the Rocker Arm and the Feeler Gauge is Placed Between the Rocker Arm and the Valve Top where the Rocker Arm Pushes on the Valve.
>>***BE SURE TO TIGHTEN THE ADJUSTER LOCK AFTER YOU HAVE THE PROPER VALVE CLEARANCE***
>>I have had Better Performance Out of the Mowers and Less Burnt Valves Using these Settings. Be Sure the Piston is at TDC on the Compression Stroke.**
>>If you Remove the Valve Cover and then Turn the Engine by Hand, you can Watch the Intake Valve Movement. When the Intake Valve Closes, the Piston will Just Starting the Compression/Power Stroke.
>>On Some Engines you can Us a Straightened Coat Hanger and Feel the Piston.
>>Be Careful and Don't Jam the Wire in the Cylinder. Usually the Piston will Push the Wire Out of the Spark Plug Hole with No Problems.
>>You can View a Breakdown/IPL of this Engine at this Site Addy, http://www.smallenginepartswarehouse.com/parts.asp and Select the Shop Online Parts Look Up. Then Select the Model Tab. Then Select the OEM and Enter the Model (5 or 6 Digits) and Type Numbers (first 4 digits Only). Example: 350447-XXXX. Then Double Click on the Model in the Results Area. Select Sectional Index. Now you can Select the Section of the Engine you Wish to View.
>>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. Comments and Ratings are Greatly Appreciated. Thanks.
Respectfully
John
