We recently changed the mixing chamber as it had corroded through on the side. Inside it, there was a large buildup of carbon deposits that refused to come out even at full power
. It got hard and didn't want to shift or even burn.
Diesels evidently don't thank you for treating them kindly... we've been told to run it well above the point where the turbo kicks in (4LH TE). Problem is, at that stage it is when the boat
is approaching hull speed
and the law of diminishing returns!