Universal M18 leaking oil / low oil pressure

adamv

.
May 17, 2022
69
Newport 28 mkII Bowen island
Had the engine out to change the mounts- since putting it back, on a couple occasions now:
* at cruising revs for an hour I noticed the oil pressure steadily drop from 45ish to 20.
* when I drop the revs down to idle the pressure drops to zero and the ignition buzzer comes on
* most important of all, about 2 tablespoons of oil have dripped
* the engine temp looks normal (barely a 3rd up the guage)

I can't see which gasket the oil is coming from- it's the lowest point- the back of the oil pan/ sump.

I did change the oil and filter when the engine was out- I did only tighten the filter a hard hand tight and I don't see any signs of oil dripping from it. I also changed the dipstick tube but this looks clear of oil too

Of course it's difficult to fully tell what the source is- I would need several go pros recording an hour while at high revs to really see what's going on.

Anyone with experience of solving a similar problem? I don't really want to take the engine out yet again only to find the gasket I replaced wasn't the problem one!