Goforbroke, when I am checking the float, what exactly would I be checking for. I know when the floats get stuck what a motor will do but this is not the case. Is this an adjustment that I need to check?

When it acts up try putting a jumper from the battery + to the coil + and if that clears it up you have a open somewhere,also keeping a eye on the gauges is good advice. The shift interupt switch may also cause a miss fire if it's out of adjustment.

the "backfire" is caused by an irratic
or untimed spark, due to random ignition
interruptions, if it was fuel (lean condition)
related, it wouldn't care if it was rough
or smooth out.
yes , check shift interrupt circuit also.
bypass wire to coil will also eliminate
wiring system problems.
good luck.

JTB, yes its a measurement you are checking. You measure its open and closed position. You will need to find the spec for the carb. Also check to see that it moves smoothly through its range and that the needle and seat move properly too.
jt29olhp500s- erratic spark could cause that but its rare and should also backfire through the exhaust if its that random.

It is also possible you have water in the bottem of your fuel tank that is below the fuel pick up-until you bounce it around.
Good Luck!

Is there an additive that you know of that would take any water out of the tank or is draining the only solution??

If your going to start shaking wires, especialy plug wires, please put a good heavy rubber glove on. Been there.....zap

First use a water level finder paste on a stick/dowel to be sure you have water,then suck it out with a hand vacum type oil changer thru the removed pickup tube.Try to raise the bow so all the water will run aft toward the pickup,follow up the job with a qt. of MDR "Water Zorb".