Oil change with full flush?

Possibly the previous oil analysis showed contaminants?

I've done that type of flush when I've done engine work, like valves and head work. to make sure all the "dropped" debris is removed, But its unusual IMO for a regular oil change.

N+G engineering is an excellent Cat repair shop. If you call them, speak to Gabriel and he'll remember the boat and tell you why. I could see doing a flush IF somehow water got into the oil (aftercoolers leaking etc.), after major work, or if there's bad oil samples. The total cost is very reasonable.

I have a related question. It's that time of year again and I'm about to change the oil in my 3412e's as well. I've used Rotella T4 in the past but wanted to see if anyone would recommend either a different brand or a different Shell product such as the synthetic options. I put 425 hours on the engines this past year. Thanks.

Yes, CAT 15w-40 DEO is what I use in CAT's.......Mobil would be my second choice. Rotella isn't what it used to be. That's a lot of hours in a season.

J what are your concerns with Rotella? We use it in most all our diesels motors( over 15). We use synthetic blend at 250hrs religiously. Just bought $500 more this morning

It's so good to hear of a boat getting used, however that's way too many hours to go without changing your oil. Most places recommend changing the oil each season, but that's because most boaters only put on way less than 200 hours. Check your manual for recommended intervals. If it says seasonally consider that 200 hours. Nothing wrong with Rotella. It's been the standard for a long time. Others have just gotten better. If you switch to synthetic that would be a reason to flush the motor as you'll want to get the old oil out. They don't blend.

Thanks for the feedback, Capt J and NYCAP123. Rookie mistake on not changing the oil sooner. It won't happen again!

Thanks for the suggestion, motoryachtlover. Your post reminded me that I need to do a sample oil analysis for both engines and the genset. After doing a simple internet search, I came up with Blackstone Labs. Does anyone else have any other suggestion?

Thanks in advance.

When I got a new car in 2016 the 2nd oil change was scheduled for 10,000 miles and then every 5,000 after that due to synthetic oil being changed. However with regular oil I'd stick with 3,000 although the recommendation is now for 5,000. I suspect the 5,000 recommendation for regular oils has more to do with the government and energy independence than changes in oil.

Yes CAT. Go to your local dealer and buy an S.O.S. oil sample kit, it's around $30 and comes with the sample bottle, shipping bottle, tubing, pre-paid shipping label etc. (make sure to fill out the label prior to attaching it to the sample bottle). They also sell a hand pump that the bottle screws on, also around $30. Start the motors and let them run 10 minutes, then pull the sample from each motor. I cut the sample tubing about 3" longer than the dipstick for each motor. Then just stick the bottle in the mail and you'll get e-mailed results within a couple of days.

Mobil is also the oil of choice of Cummins, MAN and other Marine diesel manufacturers.

A large DD/MTU dealer told me they've been seeing a lot more ring wear on engines running Rotella over other brands. I've personally noticed that it tends to lose 10 PSI of oil pressure after 50-100 hours on it on various motors. I stick with the manufacturers oil generally, or if not, use Mobil.......

All of the yachts I manage, the oil gets changed annually because none of my customers put those kind of hours on their yachts. I just had a set of MAN 1200's synthetic oil changed and it has 70 hours on the oil (and a year).

NYCAP- the additive packages on modern oils are acres ahead of what was 10 years or so ago and the newer engines burn much cleaner, both causing the extended mileage intervals. My expedition oil change light comes on around 7500 miles (or 1 year) and the oil looks pretty darn clean at that time if you put it on a white paper towel. You generally change oil because it is contaminated with hydrocarbons (unburnt fuel) and wear metals, not because the oil itself is bad.