This is a tricky one so any ideas will be appreciated. I have had this motor a number of years and it always seemed a little finicky at idle but ran beautifully at wot. Had to leave it sit for a while and then it would not start. So into the shop. Fortunately I had fixed it up with electric start way back, my old arm wont take it anymore.
Compressions both 120. New CDI power pack and plugs with fat blue sparks grand canyon type. Carb cleaned and rebuilt by me, that means the whole deal. Fires and runs strong on the top cylinder and idles but the bottom cylinder not running.
Pulled the Power head and replaced the lower crank shaft seal. How are we doing so far?
New round of tests same issue. Swapped the coil and wire, no change. Monitored the sparks and everything solid. Running on top cylinder only the bottom sparks are strong and consistent.
Disconnected the top Spark plug and tried to run on the lower cylinder only. Shot fuel into the carb intake and it starts but then dies even if I continue the injection of fuel. Tried starting using the carb fuel supply only and same issue, will fire and then die after a few revs. Will always start and run on the top cylinder. Both plugs show fuel but I have noticed that the wet fuel deposit on both plugs have a brown tint. Never saw that before .Could it be that a varmint has crawled in there and died. Didn't see anything in there when I took the carb off.
Any thoughts?
Compressions both 120. New CDI power pack and plugs with fat blue sparks grand canyon type. Carb cleaned and rebuilt by me, that means the whole deal. Fires and runs strong on the top cylinder and idles but the bottom cylinder not running.
Pulled the Power head and replaced the lower crank shaft seal. How are we doing so far?
New round of tests same issue. Swapped the coil and wire, no change. Monitored the sparks and everything solid. Running on top cylinder only the bottom sparks are strong and consistent.
Disconnected the top Spark plug and tried to run on the lower cylinder only. Shot fuel into the carb intake and it starts but then dies even if I continue the injection of fuel. Tried starting using the carb fuel supply only and same issue, will fire and then die after a few revs. Will always start and run on the top cylinder. Both plugs show fuel but I have noticed that the wet fuel deposit on both plugs have a brown tint. Never saw that before .Could it be that a varmint has crawled in there and died. Didn't see anything in there when I took the carb off.
Any thoughts?