C30 Engine oil puzzle

[Charles]

I am a new owner of a 1984 C30 (my first boat, excuse my ignorance) and am wondering if someone can give me some information regarding the engine oil display on the dip stick.When the boat has been sitting for some time without the engine running, I check the oil dipstick and notice the level of oil showing on the dipstick to be quite low. After inserting the dipstick back in and reading it again I now find the oil level showing on the dipstick to be at a reasonable level. I have asked several boat owners who have diesel engines in their boats for some thoughts and they come up blank or I get conflicting ideas.Can anyone give me an ideas as to what the proper level of the oil should be after the boat has been sitting for a while.Thanks.

 

[John Visser]

Me too!

I hae exactly the same experience with the Universal M25 in my C-36. After the engine sits, when I first pull the stick, it is clean - no oil. I wait a second, re-insert it, and find the correct oil level. I suspect that during running, a vacuum is created in hte crankcase, perhaps momentarily, that sucks the oil out of hte dipstick tube, and since the stick seals the top, the oil cannot re-enter the tube until the seal is broken by pulling the stick. Comments?jv

 

[John]

Yes

I concur and for that reason always take the reading several times before I trust it.