:smt100In my 2000 410 da I have 2 7.4 mags they both sound and proform well but the starboard engine after it warms up ,the oil pressure slowly drops from 40 to 20. So I changed the oil with 25/40 as recomended by merc. and the oil pressure then stayed at 40 lbs. for the rest of the day wich was only a couple more hours of opperation. Then the next time I used the boat was a week later, the oil pressure was back to dropping to 20 lbs. after warm up. Does any one know whats going on or any ideas???? I have a bad feeling about this, hopeing i'm wrong. Gus
low oil pressure
- Thread starter beachnut
- Start date
tdappleman
Active Member
- Dec 17, 2007
- 1,608
- Boat Info
- 1996 270 Sundancer
- Engines
- New twin 4.3's - 235hp each with Alpha 1 Gen 2 Drives
What kind of oil filters are you using?
capecodcruiser
Active Member
how much does it "use"? Yes, engines do burn/use oil, but excessive use is a sign of things to come. The beauty of a Chevy/GM motor is you can go for a long time with a little oil usage. Just keep it properly filled. Lot cheaper than a rebuild. The other thing is to hook up a known mechanical gauge to verify the low numbers on your dash gauge. Electric senders are known to be finicky and it is nice to have a back up test for so you can compare the 2. Good luck and don't freak out yet. Also, what is your pressure at running speed? A norm is 10lbs/1000RPM. That is just a benchmark, different engines require different settings but I have found that to be a safe margin of error.
I am going back to the lake next weekend and the first thing I am going to do is to put a mechanical guage on the engine where the sender is on the block. Thank you for all of your imput and ideas. Gus aka beachnut
