Small Engines (Lawn Mowers, etc.): B&S 18HP - Hard starting/Stops Running, air mixture, speed jet

Question
Hi John,
As you suggested, I took the carburetor apart and soaked it overnite. I wash it in water and blow all passages out. It started and ran little longer but was running uneven and backfired and stalled out. I tooked the high speed jet out and cleaned that also. Still no luck. Starts briefly but stalls. When choked, gas is spitting out the carb. Very early in this process I unscrewed the governor screw/linkage and reassembled it. Could this be the problem and if so, how do I set it properly. Please advise your thoughts. I appreciate your help!

Kevin

Answer
Hello Kevin:

I was Re-Reading our Past Conversations and I want to Make Sure I am Understanding where we are. The Engine Now Starts and Runs Just Uneven and Backfiring.  When we First Started it was Starting and Running a Moment and Quit. Are we Sure Both Cylinder are Firing? If Yes, OK. The Governor Setting needs to be Set; but the Engine Would Run Either Full Open or at Idle Only. We can Set this After we Locate the Main Problem and Correct it. The Governor Setting is Simple and Effects Only the Speed of the Engine, Not the Starting and Running. We Need to Check the Idle Air Mixture Screw. Turn it Full In and then Reverse 1 1/2 Turns. If this Is Correct, then you Need to Check for a Sticking Valve in One of the Cylinders. Remove the Blower Housing and Remove the Cylinder Head on the 75PSI Side of the Engine. Check the Valves for Sticking or Signs of Improper Seating to the Valve Seat. The Intake Valve Seat will be Discolored and Dark Not Bright and Shiny. The Exhaust will be Shiny Brown and Smooth. Check the Valve Seats and See if Any Look like they are Moving Inside the Aluminum Housing. I have Had Several that the Valve Seat Came Loose and Wore the Block. Do Not Give Up. We can Locate the Cause and Get it Going. Locating this Problem is Not Simple. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John