maybe you need to add a foil to you lower unit or transom wedges to eliminate the porpising.
my used 16' aluminum Express came with a tail on the Yamaha C40TLRX motor.
I removed it and had to get my brother to sit on the front of the boat to stop the porpising.
I put the tail back on
Not that it will help you, but I did find my brothers C60 had a twisted shift shaft and a bent thru pin in the output shaft some years ago apparently from someone trying to shift it while the motor/shafts were not turning to help the dogs line up
if the shifter and motor are in the neutral...
that did not answer my question, does the motor overheat if it is kept running for some length of time?
but smoke should not be coming out of the place water should be coming out of.
is that smoke coming out right after startup of the motor?
or is it steam you are seeing after the motor has...
do those motors have fuel coolers ?
sounds like you VST is boiling off the fuel in there causing a too rich condition in the intake, so you have to add more air for it to burn.
and pumping the bulb fills the VST so that pump can pressure up the rail
take the sheared pin to the machine shop, they can test to see what it is made of, and make a few for you.
I know trolling motor pins are SS
or order them from e bay since you say you can find them on there
the light tells you when the spark is happening.
idle timing is usually ATDC (after top dead center) it should advance to BTDC( before top dead center) to be able to burn the extra fuel at higher RPM
there is a reason they give you the specs in the service manual( so you can check it)
No fuel should be flowing thru the main jet into the motor during idle.
as I said check to make sure the timing is advanceing as the extra fuel starts hitting the motor.
or just tak it into a shop to let them fix it
