QuestionHello, I have read some past posts and I "think" I have it narrowed down.
Problem: gas is leaking out of air intake
Question: how do I know if the float needle is properly seated?
It goes back into the hole. The float does not seem to have a leak. I checked the carburetor and it is clear of debris (at least I can blow and spray carb cleaner through it.
I'm kind of green with this, but can follow directions well.
Thanks for your time. This service you provide is awesome!
AnswerHello Trevor:
Thanks for the Compliments about All Experts. Most of the Experts here Try Hard to Assist. From your Description it Sounds like the Carburetor Float Needle Valve is Not Seating Correctly. I have a Table Set Up and a Special Glass Bowl that is Used to Watch the Gas Flow through the Inlet Port with the Float Down and with the Float Up that is Used to Check Float Needle Valves Before the Carbuetor Bowl is Attached to the Carburetor and the Carburetor is Installed Onto the Engine. What Happens when the Needle Valve is Not Seating Correctly is the Rubber Tipped Needle is Not Sealing the Inlet Port when the Float Pushes the Needle Into the Carburetor Inlet Port. Usually Replacing the Needle Valve Correct the Problem, but I Always Suggest to Questioners and Customers to Install a Manual Cut Off valve and Turn Off the Gas FLow to the Carburetor when the Unit is Not Being Used. Some Model Carburetors have a 2 Piece Needle and Seat Kit. This Contains a O-Ring Seat and a All Metal Needle Valve. You Cannot Change from 1 Style Needle Valve (Rubber Tipped Needle Valve and 2 pc Short All Metal Needle Valve and Seat) to the Other. I am Including the Instruction Files that May Assist you with this Problem. 1- The Following is an Instruction File I Made for this Repair. Any Input Concerning the File is Appreciated. Depending on the Engine Model, Usually the Gas in the Crankcase Oil or White 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. 8- Some of these Mowers have a Pickup Tube. Remove the Pickup Tube and Ensure the Tube Screen/Filter is Clean and the Tank Does Not have Trash in it. You can View a Breakdown/IPL of this Engine at this Site Addy, http://www.outdoordistributors.com/ and Select the T. Then Select Tecumseh. Then Select Don't have Part Numbers. Then Enter the Model Numbers OHV145-203803A. Then Select your Model and Download the File for Online Viewing. The Cost of the Cleaning Solution I Use is $30.00us @ Gallon (I Use Gunk). The Gallon Can Comes with a Tray for Small Parts and the Carburetor Fits Nicely. Most Times a Carburetor can be Soaked and Cleaned and with the Float, Needle Valve and Other Carburetor Components being Soaked in the Cleaner with the Carburetor Body; there are No Parts to Replace on this Carburetor. If you Soak and Clean this Carburetor and the Float Needle Valve Still Does Not Stop the Gas Flow Properly, then Purchase a Needle and Seat Kit and Replace it. The Following is a Basic File I Made for Cleaning Carburetors. Any Input is Appreciated. The Most Common Cause is; The Carburetors Internal Passages are Restricted by Varnish that Gas Forms Over Time. This Varnish is in Layers. To Properly Remove this Varnish you have to Soak the Carburetor. The Following is a General Instruction File for Carburetor Cleaning. Even though the Carburetor Looks Clean, the Internal Passages May be Restricted with Varnish that Gas Causes to Build Up over Time. I Suggest you Make Sure the Gas is Free Flowing to the Carburetor Inlet Port (if the Model does Not have a Fuel Pump). If the Gas is Free Flowing to the Inlet Port, 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 (if Applicable), Float Pin (if Applicable), Float (if Applicable), Needle Valve and Needle Valve Seat if Applicable. This is a Flat O-Ring Located in the Inlet Port the Float Needle Rests in. Use a Strong Wire with a Slight Bend to Remove the Old Seat. Sometimes a Small Pocket Screw Driver can be Use Also. The New Seat will have a Slightly Beveled Side and a Flat Side. The Flat Side goes Towards the Carburetor Body when Inserted into the Inlet Port. Spray the Seat with Spray Lubricant to make Installation Easier. The End of a Drill Bit that is Slightly Small than the Seat can be Use as an Insertion Tool. Wear Gloves or Use a Rag when Handling the Sharpened End of the Drill Bit. Remove Any Adjustment Screws that Go Into the Carburetor Body. The Welch Plugs Do Not have to be Removed. If you are Able to Remove and Disassemble the Carburetor and Keep the Gaskets Intact, then Usually these Gaskets can be Reused. Even the O-Ring Around the Bowl can be Reused if it is Not Broken. The Only Parts you May Need to Replace is the Float Needle Valve (and Seat if Applicable). The Float Needle Usually is Not Replaced Unless it is Not Operating Properly (the gas flow not shutting off and the carburetor is Flooding). Do Not Remove the Main Nozzle. This is a Pressed Fit and Removal is Not Required for Cleaning. Soaking and Blowing the Carburetor Out After Soaking will Clean the Nozzle. Once Disassembled, 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.*** (Do Not Use High Pressure Air for the Zama Carburetors, they have Check Valves for the Primer and these are Usually Blown Out of the Carburetor if Not Careful. Allow the Zama Carburetor to Set on a Drip Pan and Dry)***. ****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 Nearest 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 This Carburetor has a Single Air Adjustment (Except Tank Mounted 9200 Model Carburetors), 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 Throttling from Idle to Full Throttle. For the 9200 Model Tank Mounted Carburetor Adjust the Air Mixture Screw Full In, then Reverse 1 1/2 Turns. Set the Throttle Lever to Full Throttle and Start the Engine. Now Carefully Use 1 Finger and Open the Throttle Plate and Over Rev the Engine Slightly. If the Engine Over Revs and Does Not Struggle to Over Rev, then the Carburetor is Set. If the Engine Struggles to Over Rev, then Turn the Adjustment Screw In 1/4 Turn and Repeat the Over Rev Test. If you Adjust to 1/2 Turns In and the Engine Still Struggles to Over Rev, then Return the Adjustment Screw to 1 1/2 Turns Out from Snug and Turn the Screw Out 1/4 Turn. Do the Over Rev Test. Continue this Process Until you have the Engine Over Revving without Struggle. By Adjusting the Carburetor on this Style Carburetor Until the Engine Over Revs without Struggle, you have Adjusted the Air Mixture to the Best Possible Setting. This file was Intended to Give you the Basic Carburetor Cleaning Instructions and May Not Reflect Your Carburetor Components. If you have Questions, Please Ask. 3- Have you Noticed that Over the Past 10 Years Most of the Push Mower have a Cut Off Valve? The Valve was Installed because there are Many of these Carburetors and Carburetor Kits that have a Needle that Does Not Seat Correctly and the Cut Off Valve has to be Turned Off when the Unit is Not Running to Stop this Problem. Is the Gas Tank Cap Venting the Tank Properly? If Pressure Builds in the Tank, it will Push Open the Carburetor Needle Valve and Cause this Problem. 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. Comments and Ratings are Greatly Appreciated. Thanks.
Respectfully
John
