Oil pressure

[Paddy]

A month into ownership of the boat and there are a few things I need clarification on. Prior to ownership, the 315hp Yanmar (590 hours) was completely serviced by the dealer, valve adjustment, timing belt, impeller, fluids, zincs, etc. Oil was changed with Rotella 10W-40 and Yanmar filters were used. The surveyor did mention that the oil pressure was fine during the sea trial.

First, is it normal to have the low oil pressure light on when i turn the key but do not start it? I start and it goes off immediately and the Beede gauge goes to 35ish. Once warm, the pressure is around 10-15 at idle and around 40-45 at 3200.

While searching for answers on this topic, a few posters mentioned making sure the dipsticks were seated. Is there more than one oil dipstick and where? When I checked the tranny dipstick, pressure was released. Short of snugging it back on, am I missing any other steps.

Boat runs fine and seems very quiet, but I would like some assurance or warning if I am missing something.

Thanks

[RobS]

Just an FYI: Rotella is 15W-40, not 10W-40. Didn't want you looking for the wrong stuff when you go changing your oil next.

Yes, oil light should do exactly what it is doing. When you energize it without the engine running it is telling you that you have no oil pressure, once you start the engine the oil pressure builds and satisfies the oil pressure warning switch.

Some 6LP's (300/315s) were equipped with 2 dipsticks. The optional dipstick is tucked in on the starter side of the engine, above the starter (under the oil cooler). This would be starboard side on an engine box model, port side on an FD.

[Paddy]

Thanks Rob. I did make a mistake, its 15w-40 Rotella, the marina left a half of jug for me. I found the oil ranges in the manual and it says .03 MPa or 4.5 psi at idle and .44 MPa or 64 psi at 3800. The low end is there, although I do not like looking at a gauge that reads that low. The upper came in around mid 50's, so I think I am fine. Already clocked 35 hours this month and the oil level is the same and crystal clear, but I will continue to monitor.

[carolmarie]

Rob:
Funny story about the oil pressure; I was at the Newport show several years ago and talked to the guys at the Mack Boring booth about the same situation, low oil gauge pressure indication at idle. ( By the way, I had my marina put a new oil sender unit on because of my concern; some $150 later! It didn' help.) Mack Boring's response: " Yanmar furnishes gages that normally are used for commercial diesel applications and therefore do not idle very often hence the needle is not often in the red zone. Don't worry about it. The key point is that the low oil pressure annunciation alarm does NOT sound." They told me not to be concerned at idelling in the red (so long as there is no alarm) but if it would make me feel better they would send me an updated Yanmar replacement gauge that -and, yes, you guessed it - they simply eliminated the red zone markings and changed them to blue. Got the new gauge (free!) a few days later.
Regards,
carolmarie, 2001, 28TE, 6LP-STE.
PS Never did install it!

[Paddy]

It's comforting to read that you are living with the same gauge readings. A marina neighbor with 50 years of boat experience told me the same thing, very low at idle and 35-40 is perfectly normal...not to worry, but when that gauge is sitting close to zero, it makes me a bit anxious. Thanks for your response, I will sleep better now!