That’s a good point you make.
The bottom of the bellhousing is the lowest point, maybe it’s just collecting there. However, I can’t see any track marks, but maybe that’s not so unusual. The only other significant oil leak I’ve experienced was cruising the East coast of Australia. Motored into Yamba, did an engine check - big pool of oil on the floor, with no obvious leakage point at all. Local engineer looked at it sagely, shaking his head and suggesting we probably need a new engine. I called my regular engineer in Sydney, who asked a few questions, and diagnosed the problem in a couple of minutes.
It was a minuscule split in the rubber cap of the oil evacuation tube. No sign whatsoever of any leakage from it, however one new rubber cap and one cable tie later, problem sorted.
We had been motor-sailing on a heel. The leaking oil was vapour and simply condensed on the floor of the engine bay. No drips, no tell-tale signs at all on the engine.
I will look more closely at the turbocharger as you suggest.
Motoring at 1650 today was very gentlemanly! Not much sea, 8knots, quiet engine, good economy. Such a shame it’s bad for the motor!
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