Yeah, it had a primer. No hard starts, was running fine.
That is why I don't like primers. Primers eliminate the symptom (hard starting), but
they do not fix the engine problem that caused the hard starting.
Back in the late 80's and early 90's when Jet ski's were popular, customers would bring
in their 440/550's for tune ups before a vacation, and it was a complaint that the tune
and service was a waste of money.
The problem was fixed by carefully evaluating the
Jet Ski before a repair order was written.
It didn't make sense to spend money on a T&S, when the engine needed an overhaul.
The 440/550s became infamous for leaking front main seals. Nearly all of the front main
seals leaked vacuum, but when the front main seal leaked a moderate to high amounts
of vacuum (4.5 to 7.5hg), the leaking main seal would cause carb problems like hard starting.
With the vacuum side of the main seal worn out, the mains seal sucked metal debris (from
the starter), rust, and water directly into the front main bearing.
Then the front main seals would leak up to 7.5psi (average crankcase pressure)
Your Yamaha suffered similar problems (possibly for a couple years). The motor mounts is
a common failure that can be caused by wake jumping.
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For your remaining watercraft I encourage you to ask more questions, and maybe you
will be able too recognize a problem before it becomes serious.
Bill M.
86' thru 90' pp 550's had more problems than any 440, and early 550. But they all came
with main seals that started leaking vacuum after 2hrs, during break in.
