16HP V-Twin. Engine only runs on Cylinder #1 . Pulled spark plug on Cylinder #2 ground it to block and crank engine, plug fires fine(Plugs are new OEM). Seems when plug is threaded into head it quits firing. Swapped plugs to rule out faulty plug, same result . Carb is new and plug is wet when removed from head so I know fuel is there. One note: old ignition coil wire melted against engine so key switch would not turn engine off. I replaced wire with new OEM wire and when installed to coils there is NO spark out of either coil so I cannot run engine with wire connected. (defective diodes?). Also touching the #2 plug wire insulation when running I get zapped. But why would the plug not fire when threaded into head? No visible arcing from plug wire to any ground seen.??

B&S Vanguard Horizontal 16HP

Model 303447 0348-02

 

Does the skipping cylinder have compression? Remove the valve cover and see if the valves are working. You may have to use an inline spark tester from the auto parts store to test if there is in fact spark while the engine is turning.

 

OK I pulled the valve cover and vwallah, the rocker arm fastener came loose just enough to dump both pushrods down into the well. They were not bent so I reinstalled them and set lash up to spec. Did the same for the other cylinder, clearances way too wide. She runs like a champ now firing happily on both cylinders! Thanks for the help.

 

Great! Glad we could help!
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