JR North wrote:
From what I see, the second picture shows an increasing combustion
chamber temp from top to bottom, with the top cyl looking good, the
middle one so-so, and the bottom one critical, burned out and detonated
to pieces. This looks vwery much like a cooling issue in the bottom of
the motor, possibly also a decreasing lack of oil spray to the pistons.
My 02
JR


Come on JR this is one step away from the deny it's even an E-Tec defense:-)

I guess I shouldn't even help the sad sack ripoff E-Tec spruikers with a
reasoned explanation but; here there is even a theory as to "why" this
one when fed a lean poorly atomised improperly ignited mixture detonated
itself to death & no it's not the brand name of approved oil.

The growth shown in the bottom left of the last pic?? if the boat were
taken out with that on it & is a big heavy boat to start with, that
would almost certainly load the prop up even more at low to mid revs
(i.e.lean/repeat spark mode).

The user would apply whatever throttle was needed to attain/maintain the
usual nose high big drag "no wake" speed & there you have it, kaboom:-).
Very very lean at "power" (not full but even so) on a poorly atomised,
inaccurately ignition timed charge??.

As the boards are saying they just keep throwing new powerheads at them
& pricing them higher than the competition so those silly enough to pay
(we even have our own in house NG demo dummy:-)) subsidise the claims of
the others:-).

Sorta socialised engine development ..... hey don't be rude: I didn't
even mention the French!!!

K