I'm a first-time boat owner, so I'm learning as I go. We've taken the
boat out twice, and it started (after a little while), then ran pretty
good. It is a 1987 Fabuglas vessel, with a 90HP Johnson outboard - SN
7569852. There are separate gas and oil tanks, so it automatically
mixes what it needs.

Today, when trying to start the motor, it will not prime. I can
squeeze the prime bulb for hours, and the fuel seems to go into the
motor, then suck right back out. My brother mentioned that last week
when we had the boat out, the prime bulb seemed to "squeeze flat, then
not expand again".

After some playing today, we looked at the fuel filter, but there was
very little fuel in it. It looked to be mostly full of air. When
squeezing the primer, I could see fuel going into the filter, then
sucking right back out of the filter back towards the tank. Needless
to say, cranking the engine did just that - CRANK. It never turned
over - no fuel. At least we know the battery is good (cranked and
watched it try to start for a good 15-20 minutes off and on. Water is
pumping through the system, but no fuel...)

What am I missing? Is there a valve sticking somewhere? Is the primer
ball shot? I tried venting the fuel tank by opening the main fill cap
(in the event the vent line is blocked by mud or such), but that didn't
help either. Any advice would be most appreciated. Thanks//Rod