a t50 pushing a 20 ft pontoon?
not much motor .
have you looked at what other people are pushing a boat like yours with?
also what prop they used?
look at yamaha performance bulitens online to see if they list a T50 for a toon like yours ,
and if so what prop that used.
was that a Yamaha service manual or an aftermarket one?
Boscoe said the Yamaha service manual and owner's manual
by the way you mentioned copper ring on some plugs,
copper and aluminum do not get along well touching each other
simple to start draining the tank slowly and see when it refills
but I would think your service manual for your motor would tell you about how far it would move to set the switch
sounds like a lean sneeze.
and pump is not doing its job if pumping the primer bulb helps.
check to make sure pump is still good,
and the idle jets/passages are feeding the fuel needed for each cylinder
idle timing is After TDC, ( retarded timing)
WOT timing is Before TDC.(advanced timing)
guessing at what the timing is actually doing by looking at the none functional wiper does not help at all
if timing is not close to correct with the wiper pointed at the marks, then I would say it needs replacing.
what does the timing light show the timing at when wiper set to where the motor will run?
I had to replace my CDI due to the idle timing retarded 14 Deg when set to the marks on CDI.
others had jacked with all the carb linkages just to get it to idle, WOT was as problem.
and it did not help that they had drilled out the main jets too.
took me a long time to finally get the motor...
charge every night or get a small generator.
or solar panels.
please do not disturb everyone else with your loud noise on the water,
that would also be helpful with your battery drain
