hello , my brother has a 73 4 horse johnson , bought in oct 2011, ran great for that month started on first or second pull then got put up for winter,a few months later took out was hard to start then would run for 5-10 min and die.we changed fuel pump, water pump,gas tank ,lines and fittings. then found out the primer bulb had disintergrated (sp). took it to a boat shop and had carb cleaned and rebuilt.
it runs and sounds great when in a barrel of water but when on the boat at the lake it still runs maybe 5 min then dies and takes a long time to start again , has to turn the slow and fast knobs all the way in then back out if i remember around 3/4 turn on top one and 1/2 turn on the bottom. then sometimes it will start again.this year when took out to get ready still doing it. but noticed after running for 15 min and died and would not restart, top plug looks wet bottom plug looks bone dry. is it only running on 1 cylinder? or what else could it be . joe
it runs and sounds great when in a barrel of water but when on the boat at the lake it still runs maybe 5 min then dies and takes a long time to start again , has to turn the slow and fast knobs all the way in then back out if i remember around 3/4 turn on top one and 1/2 turn on the bottom. then sometimes it will start again.this year when took out to get ready still doing it. but noticed after running for 15 min and died and would not restart, top plug looks wet bottom plug looks bone dry. is it only running on 1 cylinder? or what else could it be . joe