406777-0128e1 --> Briggs Stratton Intek -V-twin - Scott’s lawn tractor
Engine ran perfectly, had a bad sump pan gasket leak, reassembled engine but governor went bad ... and the governor had to be changed.
--
Open it up again and change governor, replaced gasket, bolts, mounted the engine and then the surging began.
Cleaned carburetor, noting
Rebuilt carburetor, new seals, clean everything - nothing
Engine runs semi-O.K, without air filter, once the filter is on it runs rough, idle up and down
Spark plugs are black both cylinders
Replaced carburetor with OEM Briggs carburetor and now the engine surges and runs rich ...
I have checked for air leaks by spraying carb cleaner around carb gaskets, no change on engine behavior.
Besides the engine behaves air starved, when placin brand new or old air filter the behavior is worst.
Replaced spark plugs, with recommended brand /model / gap
Checked governor setting (governor clock wise max, throttle counter clock wise max
Checked valves -- some say .0004 1/4 inch pass TDC compression. When first open the valve cover, I measured and vales were 0.008 intake, and 0.009 exhaust
I have set them anywhere from .004 intake to .008 exhaust, and the best setting found so far is both at 0.005 TDC compression.
Valve guides are in place
I notice engine fuel pump when first starting, when the hoses were empty while priming the gas, it did shoot out some droplets of gasoline from the center hole on the pump, but once the hose have fuel the leaking stops.
The ONLY thing I have not changed for a new component is the gas pump, it has good flow and it works.
If I clamp the fuel line, the engine runs perfectly for the last 30 seconds or so when it is consuming the last droplets of gasoline.
I did not touch the timing gear when installing the new governor, but I did not actively check that the timing dots were aligned.
See videos with sound => https://www.amazon.com/photos/shared/F2QPA9t9RR2QMJxwDP4vmA.3sTrF0xnUjSGwWpoFTDaXz
Ideas anyone?
Engine ran perfectly, had a bad sump pan gasket leak, reassembled engine but governor went bad ... and the governor had to be changed.
--
Open it up again and change governor, replaced gasket, bolts, mounted the engine and then the surging began.
Cleaned carburetor, noting
Rebuilt carburetor, new seals, clean everything - nothing
Engine runs semi-O.K, without air filter, once the filter is on it runs rough, idle up and down
Spark plugs are black both cylinders
Replaced carburetor with OEM Briggs carburetor and now the engine surges and runs rich ...
I have checked for air leaks by spraying carb cleaner around carb gaskets, no change on engine behavior.
Besides the engine behaves air starved, when placin brand new or old air filter the behavior is worst.
Replaced spark plugs, with recommended brand /model / gap
Checked governor setting (governor clock wise max, throttle counter clock wise max
Checked valves -- some say .0004 1/4 inch pass TDC compression. When first open the valve cover, I measured and vales were 0.008 intake, and 0.009 exhaust
I have set them anywhere from .004 intake to .008 exhaust, and the best setting found so far is both at 0.005 TDC compression.
Valve guides are in place
I notice engine fuel pump when first starting, when the hoses were empty while priming the gas, it did shoot out some droplets of gasoline from the center hole on the pump, but once the hose have fuel the leaking stops.
The ONLY thing I have not changed for a new component is the gas pump, it has good flow and it works.
If I clamp the fuel line, the engine runs perfectly for the last 30 seconds or so when it is consuming the last droplets of gasoline.
I did not touch the timing gear when installing the new governor, but I did not actively check that the timing dots were aligned.
See videos with sound => https://www.amazon.com/photos/shared/F2QPA9t9RR2QMJxwDP4vmA.3sTrF0xnUjSGwWpoFTDaXz
Ideas anyone?
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